mirror of git://gcc.gnu.org/git/gcc.git
7150 lines
211 KiB
C
7150 lines
211 KiB
C
/* Expands front end tree to back end RTL for GCC.
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Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
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1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
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2010, 2011, 2012 Free Software Foundation, Inc.
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This file is part of GCC.
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GCC is free software; you can redistribute it and/or modify it under
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the terms of the GNU General Public License as published by the Free
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Software Foundation; either version 3, or (at your option) any later
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version.
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GCC is distributed in the hope that it will be useful, but WITHOUT ANY
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WARRANTY; without even the implied warranty of MERCHANTABILITY or
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FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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for more details.
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You should have received a copy of the GNU General Public License
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along with GCC; see the file COPYING3. If not see
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<http://www.gnu.org/licenses/>. */
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/* This file handles the generation of rtl code from tree structure
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at the level of the function as a whole.
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It creates the rtl expressions for parameters and auto variables
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and has full responsibility for allocating stack slots.
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`expand_function_start' is called at the beginning of a function,
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before the function body is parsed, and `expand_function_end' is
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called after parsing the body.
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Call `assign_stack_local' to allocate a stack slot for a local variable.
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This is usually done during the RTL generation for the function body,
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but it can also be done in the reload pass when a pseudo-register does
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not get a hard register. */
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#include "config.h"
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#include "system.h"
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#include "coretypes.h"
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#include "tm.h"
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#include "rtl-error.h"
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#include "tree.h"
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#include "flags.h"
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#include "except.h"
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#include "function.h"
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#include "expr.h"
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#include "optabs.h"
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#include "libfuncs.h"
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#include "regs.h"
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#include "hard-reg-set.h"
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#include "insn-config.h"
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#include "recog.h"
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#include "output.h"
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#include "basic-block.h"
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#include "hashtab.h"
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#include "ggc.h"
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#include "tm_p.h"
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#include "langhooks.h"
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#include "target.h"
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#include "common/common-target.h"
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#include "gimple.h"
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#include "tree-pass.h"
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#include "predict.h"
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#include "df.h"
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#include "vecprim.h"
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#include "params.h"
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#include "bb-reorder.h"
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/* So we can assign to cfun in this file. */
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#undef cfun
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#ifndef STACK_ALIGNMENT_NEEDED
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#define STACK_ALIGNMENT_NEEDED 1
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#endif
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#define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
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/* Some systems use __main in a way incompatible with its use in gcc, in these
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cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
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give the same symbol without quotes for an alternative entry point. You
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must define both, or neither. */
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#ifndef NAME__MAIN
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#define NAME__MAIN "__main"
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#endif
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/* Round a value to the lowest integer less than it that is a multiple of
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the required alignment. Avoid using division in case the value is
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negative. Assume the alignment is a power of two. */
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#define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
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/* Similar, but round to the next highest integer that meets the
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alignment. */
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#define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
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/* Nonzero once virtual register instantiation has been done.
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assign_stack_local uses frame_pointer_rtx when this is nonzero.
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calls.c:emit_library_call_value_1 uses it to set up
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post-instantiation libcalls. */
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int virtuals_instantiated;
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/* Assign unique numbers to labels generated for profiling, debugging, etc. */
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static GTY(()) int funcdef_no;
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/* These variables hold pointers to functions to create and destroy
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target specific, per-function data structures. */
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struct machine_function * (*init_machine_status) (void);
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/* The currently compiled function. */
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struct function *cfun = 0;
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/* These hashes record the prologue and epilogue insns. */
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static GTY((if_marked ("ggc_marked_p"), param_is (struct rtx_def)))
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htab_t prologue_insn_hash;
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static GTY((if_marked ("ggc_marked_p"), param_is (struct rtx_def)))
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htab_t epilogue_insn_hash;
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htab_t types_used_by_vars_hash = NULL;
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VEC(tree,gc) *types_used_by_cur_var_decl;
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/* Forward declarations. */
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static struct temp_slot *find_temp_slot_from_address (rtx);
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static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
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static void pad_below (struct args_size *, enum machine_mode, tree);
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static void reorder_blocks_1 (rtx, tree, VEC(tree,heap) **);
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static int all_blocks (tree, tree *);
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static tree *get_block_vector (tree, int *);
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extern tree debug_find_var_in_block_tree (tree, tree);
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/* We always define `record_insns' even if it's not used so that we
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can always export `prologue_epilogue_contains'. */
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static void record_insns (rtx, rtx, htab_t *) ATTRIBUTE_UNUSED;
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static bool contains (const_rtx, htab_t);
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static void prepare_function_start (void);
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static void do_clobber_return_reg (rtx, void *);
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static void do_use_return_reg (rtx, void *);
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static void set_insn_locators (rtx, int) ATTRIBUTE_UNUSED;
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/* Stack of nested functions. */
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/* Keep track of the cfun stack. */
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typedef struct function *function_p;
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DEF_VEC_P(function_p);
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DEF_VEC_ALLOC_P(function_p,heap);
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static VEC(function_p,heap) *function_context_stack;
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/* Save the current context for compilation of a nested function.
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This is called from language-specific code. */
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void
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push_function_context (void)
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{
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if (cfun == 0)
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allocate_struct_function (NULL, false);
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VEC_safe_push (function_p, heap, function_context_stack, cfun);
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set_cfun (NULL);
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}
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/* Restore the last saved context, at the end of a nested function.
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This function is called from language-specific code. */
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void
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pop_function_context (void)
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{
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struct function *p = VEC_pop (function_p, function_context_stack);
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set_cfun (p);
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current_function_decl = p->decl;
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/* Reset variables that have known state during rtx generation. */
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virtuals_instantiated = 0;
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generating_concat_p = 1;
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}
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/* Clear out all parts of the state in F that can safely be discarded
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after the function has been parsed, but not compiled, to let
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garbage collection reclaim the memory. */
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void
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free_after_parsing (struct function *f)
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{
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f->language = 0;
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}
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/* Clear out all parts of the state in F that can safely be discarded
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after the function has been compiled, to let garbage collection
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reclaim the memory. */
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void
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free_after_compilation (struct function *f)
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{
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prologue_insn_hash = NULL;
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epilogue_insn_hash = NULL;
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free (crtl->emit.regno_pointer_align);
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memset (crtl, 0, sizeof (struct rtl_data));
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f->eh = NULL;
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f->machine = NULL;
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f->cfg = NULL;
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regno_reg_rtx = NULL;
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insn_locators_free ();
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}
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/* Return size needed for stack frame based on slots so far allocated.
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This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
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the caller may have to do that. */
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HOST_WIDE_INT
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get_frame_size (void)
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{
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if (FRAME_GROWS_DOWNWARD)
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return -frame_offset;
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else
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return frame_offset;
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}
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/* Issue an error message and return TRUE if frame OFFSET overflows in
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the signed target pointer arithmetics for function FUNC. Otherwise
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return FALSE. */
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bool
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frame_offset_overflow (HOST_WIDE_INT offset, tree func)
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{
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unsigned HOST_WIDE_INT size = FRAME_GROWS_DOWNWARD ? -offset : offset;
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if (size > ((unsigned HOST_WIDE_INT) 1 << (GET_MODE_BITSIZE (Pmode) - 1))
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/* Leave room for the fixed part of the frame. */
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- 64 * UNITS_PER_WORD)
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{
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error_at (DECL_SOURCE_LOCATION (func),
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"total size of local objects too large");
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return TRUE;
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}
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return FALSE;
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}
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/* Return stack slot alignment in bits for TYPE and MODE. */
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static unsigned int
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get_stack_local_alignment (tree type, enum machine_mode mode)
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{
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unsigned int alignment;
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if (mode == BLKmode)
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alignment = BIGGEST_ALIGNMENT;
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else
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alignment = GET_MODE_ALIGNMENT (mode);
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/* Allow the frond-end to (possibly) increase the alignment of this
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stack slot. */
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if (! type)
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type = lang_hooks.types.type_for_mode (mode, 0);
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return STACK_SLOT_ALIGNMENT (type, mode, alignment);
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}
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/* Determine whether it is possible to fit a stack slot of size SIZE and
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alignment ALIGNMENT into an area in the stack frame that starts at
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frame offset START and has a length of LENGTH. If so, store the frame
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offset to be used for the stack slot in *POFFSET and return true;
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return false otherwise. This function will extend the frame size when
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given a start/length pair that lies at the end of the frame. */
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static bool
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try_fit_stack_local (HOST_WIDE_INT start, HOST_WIDE_INT length,
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HOST_WIDE_INT size, unsigned int alignment,
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HOST_WIDE_INT *poffset)
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{
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HOST_WIDE_INT this_frame_offset;
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int frame_off, frame_alignment, frame_phase;
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/* Calculate how many bytes the start of local variables is off from
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stack alignment. */
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frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
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frame_off = STARTING_FRAME_OFFSET % frame_alignment;
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frame_phase = frame_off ? frame_alignment - frame_off : 0;
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/* Round the frame offset to the specified alignment. */
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/* We must be careful here, since FRAME_OFFSET might be negative and
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division with a negative dividend isn't as well defined as we might
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like. So we instead assume that ALIGNMENT is a power of two and
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use logical operations which are unambiguous. */
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if (FRAME_GROWS_DOWNWARD)
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this_frame_offset
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= (FLOOR_ROUND (start + length - size - frame_phase,
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(unsigned HOST_WIDE_INT) alignment)
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+ frame_phase);
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else
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this_frame_offset
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= (CEIL_ROUND (start - frame_phase,
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(unsigned HOST_WIDE_INT) alignment)
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+ frame_phase);
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/* See if it fits. If this space is at the edge of the frame,
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consider extending the frame to make it fit. Our caller relies on
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this when allocating a new slot. */
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if (frame_offset == start && this_frame_offset < frame_offset)
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frame_offset = this_frame_offset;
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else if (this_frame_offset < start)
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return false;
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else if (start + length == frame_offset
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&& this_frame_offset + size > start + length)
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frame_offset = this_frame_offset + size;
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else if (this_frame_offset + size > start + length)
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return false;
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*poffset = this_frame_offset;
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return true;
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}
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/* Create a new frame_space structure describing free space in the stack
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frame beginning at START and ending at END, and chain it into the
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function's frame_space_list. */
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static void
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add_frame_space (HOST_WIDE_INT start, HOST_WIDE_INT end)
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{
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struct frame_space *space = ggc_alloc_frame_space ();
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space->next = crtl->frame_space_list;
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crtl->frame_space_list = space;
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space->start = start;
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space->length = end - start;
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}
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/* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
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with machine mode MODE.
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ALIGN controls the amount of alignment for the address of the slot:
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0 means according to MODE,
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-1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
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-2 means use BITS_PER_UNIT,
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positive specifies alignment boundary in bits.
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KIND has ASLK_REDUCE_ALIGN bit set if it is OK to reduce
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alignment and ASLK_RECORD_PAD bit set if we should remember
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extra space we allocated for alignment purposes. When we are
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called from assign_stack_temp_for_type, it is not set so we don't
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track the same stack slot in two independent lists.
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We do not round to stack_boundary here. */
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rtx
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assign_stack_local_1 (enum machine_mode mode, HOST_WIDE_INT size,
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int align, int kind)
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{
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rtx x, addr;
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int bigend_correction = 0;
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HOST_WIDE_INT slot_offset = 0, old_frame_offset;
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unsigned int alignment, alignment_in_bits;
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if (align == 0)
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{
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alignment = get_stack_local_alignment (NULL, mode);
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alignment /= BITS_PER_UNIT;
|
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}
|
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else if (align == -1)
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{
|
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alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
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size = CEIL_ROUND (size, alignment);
|
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}
|
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else if (align == -2)
|
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alignment = 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
|
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else
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alignment = align / BITS_PER_UNIT;
|
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|
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alignment_in_bits = alignment * BITS_PER_UNIT;
|
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|
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/* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */
|
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if (alignment_in_bits > MAX_SUPPORTED_STACK_ALIGNMENT)
|
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{
|
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alignment_in_bits = MAX_SUPPORTED_STACK_ALIGNMENT;
|
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alignment = alignment_in_bits / BITS_PER_UNIT;
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}
|
||
|
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if (SUPPORTS_STACK_ALIGNMENT)
|
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{
|
||
if (crtl->stack_alignment_estimated < alignment_in_bits)
|
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{
|
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if (!crtl->stack_realign_processed)
|
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crtl->stack_alignment_estimated = alignment_in_bits;
|
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else
|
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{
|
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/* If stack is realigned and stack alignment value
|
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hasn't been finalized, it is OK not to increase
|
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stack_alignment_estimated. The bigger alignment
|
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requirement is recorded in stack_alignment_needed
|
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below. */
|
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gcc_assert (!crtl->stack_realign_finalized);
|
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if (!crtl->stack_realign_needed)
|
||
{
|
||
/* It is OK to reduce the alignment as long as the
|
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requested size is 0 or the estimated stack
|
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alignment >= mode alignment. */
|
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gcc_assert ((kind & ASLK_REDUCE_ALIGN)
|
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|| size == 0
|
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|| (crtl->stack_alignment_estimated
|
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>= GET_MODE_ALIGNMENT (mode)));
|
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alignment_in_bits = crtl->stack_alignment_estimated;
|
||
alignment = alignment_in_bits / BITS_PER_UNIT;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
if (crtl->stack_alignment_needed < alignment_in_bits)
|
||
crtl->stack_alignment_needed = alignment_in_bits;
|
||
if (crtl->max_used_stack_slot_alignment < alignment_in_bits)
|
||
crtl->max_used_stack_slot_alignment = alignment_in_bits;
|
||
|
||
if (mode != BLKmode || size != 0)
|
||
{
|
||
if (kind & ASLK_RECORD_PAD)
|
||
{
|
||
struct frame_space **psp;
|
||
|
||
for (psp = &crtl->frame_space_list; *psp; psp = &(*psp)->next)
|
||
{
|
||
struct frame_space *space = *psp;
|
||
if (!try_fit_stack_local (space->start, space->length, size,
|
||
alignment, &slot_offset))
|
||
continue;
|
||
*psp = space->next;
|
||
if (slot_offset > space->start)
|
||
add_frame_space (space->start, slot_offset);
|
||
if (slot_offset + size < space->start + space->length)
|
||
add_frame_space (slot_offset + size,
|
||
space->start + space->length);
|
||
goto found_space;
|
||
}
|
||
}
|
||
}
|
||
else if (!STACK_ALIGNMENT_NEEDED)
|
||
{
|
||
slot_offset = frame_offset;
|
||
goto found_space;
|
||
}
|
||
|
||
old_frame_offset = frame_offset;
|
||
|
||
if (FRAME_GROWS_DOWNWARD)
|
||
{
|
||
frame_offset -= size;
|
||
try_fit_stack_local (frame_offset, size, size, alignment, &slot_offset);
|
||
|
||
if (kind & ASLK_RECORD_PAD)
|
||
{
|
||
if (slot_offset > frame_offset)
|
||
add_frame_space (frame_offset, slot_offset);
|
||
if (slot_offset + size < old_frame_offset)
|
||
add_frame_space (slot_offset + size, old_frame_offset);
|
||
}
|
||
}
|
||
else
|
||
{
|
||
frame_offset += size;
|
||
try_fit_stack_local (old_frame_offset, size, size, alignment, &slot_offset);
|
||
|
||
if (kind & ASLK_RECORD_PAD)
|
||
{
|
||
if (slot_offset > old_frame_offset)
|
||
add_frame_space (old_frame_offset, slot_offset);
|
||
if (slot_offset + size < frame_offset)
|
||
add_frame_space (slot_offset + size, frame_offset);
|
||
}
|
||
}
|
||
|
||
found_space:
|
||
/* On a big-endian machine, if we are allocating more space than we will use,
|
||
use the least significant bytes of those that are allocated. */
|
||
if (BYTES_BIG_ENDIAN && mode != BLKmode && GET_MODE_SIZE (mode) < size)
|
||
bigend_correction = size - GET_MODE_SIZE (mode);
|
||
|
||
/* If we have already instantiated virtual registers, return the actual
|
||
address relative to the frame pointer. */
|
||
if (virtuals_instantiated)
|
||
addr = plus_constant (Pmode, frame_pointer_rtx,
|
||
trunc_int_for_mode
|
||
(slot_offset + bigend_correction
|
||
+ STARTING_FRAME_OFFSET, Pmode));
|
||
else
|
||
addr = plus_constant (Pmode, virtual_stack_vars_rtx,
|
||
trunc_int_for_mode
|
||
(slot_offset + bigend_correction,
|
||
Pmode));
|
||
|
||
x = gen_rtx_MEM (mode, addr);
|
||
set_mem_align (x, alignment_in_bits);
|
||
MEM_NOTRAP_P (x) = 1;
|
||
|
||
stack_slot_list
|
||
= gen_rtx_EXPR_LIST (VOIDmode, x, stack_slot_list);
|
||
|
||
if (frame_offset_overflow (frame_offset, current_function_decl))
|
||
frame_offset = 0;
|
||
|
||
return x;
|
||
}
|
||
|
||
/* Wrap up assign_stack_local_1 with last parameter as false. */
|
||
|
||
rtx
|
||
assign_stack_local (enum machine_mode mode, HOST_WIDE_INT size, int align)
|
||
{
|
||
return assign_stack_local_1 (mode, size, align, ASLK_RECORD_PAD);
|
||
}
|
||
|
||
/* In order to evaluate some expressions, such as function calls returning
|
||
structures in memory, we need to temporarily allocate stack locations.
|
||
We record each allocated temporary in the following structure.
|
||
|
||
Associated with each temporary slot is a nesting level. When we pop up
|
||
one level, all temporaries associated with the previous level are freed.
|
||
Normally, all temporaries are freed after the execution of the statement
|
||
in which they were created. However, if we are inside a ({...}) grouping,
|
||
the result may be in a temporary and hence must be preserved. If the
|
||
result could be in a temporary, we preserve it if we can determine which
|
||
one it is in. If we cannot determine which temporary may contain the
|
||
result, all temporaries are preserved. A temporary is preserved by
|
||
pretending it was allocated at the previous nesting level. */
|
||
|
||
struct GTY(()) temp_slot {
|
||
/* Points to next temporary slot. */
|
||
struct temp_slot *next;
|
||
/* Points to previous temporary slot. */
|
||
struct temp_slot *prev;
|
||
/* The rtx to used to reference the slot. */
|
||
rtx slot;
|
||
/* The size, in units, of the slot. */
|
||
HOST_WIDE_INT size;
|
||
/* The type of the object in the slot, or zero if it doesn't correspond
|
||
to a type. We use this to determine whether a slot can be reused.
|
||
It can be reused if objects of the type of the new slot will always
|
||
conflict with objects of the type of the old slot. */
|
||
tree type;
|
||
/* The alignment (in bits) of the slot. */
|
||
unsigned int align;
|
||
/* Nonzero if this temporary is currently in use. */
|
||
char in_use;
|
||
/* Nesting level at which this slot is being used. */
|
||
int level;
|
||
/* The offset of the slot from the frame_pointer, including extra space
|
||
for alignment. This info is for combine_temp_slots. */
|
||
HOST_WIDE_INT base_offset;
|
||
/* The size of the slot, including extra space for alignment. This
|
||
info is for combine_temp_slots. */
|
||
HOST_WIDE_INT full_size;
|
||
};
|
||
|
||
/* A table of addresses that represent a stack slot. The table is a mapping
|
||
from address RTXen to a temp slot. */
|
||
static GTY((param_is(struct temp_slot_address_entry))) htab_t temp_slot_address_table;
|
||
static size_t n_temp_slots_in_use;
|
||
|
||
/* Entry for the above hash table. */
|
||
struct GTY(()) temp_slot_address_entry {
|
||
hashval_t hash;
|
||
rtx address;
|
||
struct temp_slot *temp_slot;
|
||
};
|
||
|
||
/* Removes temporary slot TEMP from LIST. */
|
||
|
||
static void
|
||
cut_slot_from_list (struct temp_slot *temp, struct temp_slot **list)
|
||
{
|
||
if (temp->next)
|
||
temp->next->prev = temp->prev;
|
||
if (temp->prev)
|
||
temp->prev->next = temp->next;
|
||
else
|
||
*list = temp->next;
|
||
|
||
temp->prev = temp->next = NULL;
|
||
}
|
||
|
||
/* Inserts temporary slot TEMP to LIST. */
|
||
|
||
static void
|
||
insert_slot_to_list (struct temp_slot *temp, struct temp_slot **list)
|
||
{
|
||
temp->next = *list;
|
||
if (*list)
|
||
(*list)->prev = temp;
|
||
temp->prev = NULL;
|
||
*list = temp;
|
||
}
|
||
|
||
/* Returns the list of used temp slots at LEVEL. */
|
||
|
||
static struct temp_slot **
|
||
temp_slots_at_level (int level)
|
||
{
|
||
if (level >= (int) VEC_length (temp_slot_p, used_temp_slots))
|
||
VEC_safe_grow_cleared (temp_slot_p, gc, used_temp_slots, level + 1);
|
||
|
||
return &(VEC_address (temp_slot_p, used_temp_slots)[level]);
|
||
}
|
||
|
||
/* Returns the maximal temporary slot level. */
|
||
|
||
static int
|
||
max_slot_level (void)
|
||
{
|
||
if (!used_temp_slots)
|
||
return -1;
|
||
|
||
return VEC_length (temp_slot_p, used_temp_slots) - 1;
|
||
}
|
||
|
||
/* Moves temporary slot TEMP to LEVEL. */
|
||
|
||
static void
|
||
move_slot_to_level (struct temp_slot *temp, int level)
|
||
{
|
||
cut_slot_from_list (temp, temp_slots_at_level (temp->level));
|
||
insert_slot_to_list (temp, temp_slots_at_level (level));
|
||
temp->level = level;
|
||
}
|
||
|
||
/* Make temporary slot TEMP available. */
|
||
|
||
static void
|
||
make_slot_available (struct temp_slot *temp)
|
||
{
|
||
cut_slot_from_list (temp, temp_slots_at_level (temp->level));
|
||
insert_slot_to_list (temp, &avail_temp_slots);
|
||
temp->in_use = 0;
|
||
temp->level = -1;
|
||
n_temp_slots_in_use--;
|
||
}
|
||
|
||
/* Compute the hash value for an address -> temp slot mapping.
|
||
The value is cached on the mapping entry. */
|
||
static hashval_t
|
||
temp_slot_address_compute_hash (struct temp_slot_address_entry *t)
|
||
{
|
||
int do_not_record = 0;
|
||
return hash_rtx (t->address, GET_MODE (t->address),
|
||
&do_not_record, NULL, false);
|
||
}
|
||
|
||
/* Return the hash value for an address -> temp slot mapping. */
|
||
static hashval_t
|
||
temp_slot_address_hash (const void *p)
|
||
{
|
||
const struct temp_slot_address_entry *t;
|
||
t = (const struct temp_slot_address_entry *) p;
|
||
return t->hash;
|
||
}
|
||
|
||
/* Compare two address -> temp slot mapping entries. */
|
||
static int
|
||
temp_slot_address_eq (const void *p1, const void *p2)
|
||
{
|
||
const struct temp_slot_address_entry *t1, *t2;
|
||
t1 = (const struct temp_slot_address_entry *) p1;
|
||
t2 = (const struct temp_slot_address_entry *) p2;
|
||
return exp_equiv_p (t1->address, t2->address, 0, true);
|
||
}
|
||
|
||
/* Add ADDRESS as an alias of TEMP_SLOT to the addess -> temp slot mapping. */
|
||
static void
|
||
insert_temp_slot_address (rtx address, struct temp_slot *temp_slot)
|
||
{
|
||
void **slot;
|
||
struct temp_slot_address_entry *t = ggc_alloc_temp_slot_address_entry ();
|
||
t->address = address;
|
||
t->temp_slot = temp_slot;
|
||
t->hash = temp_slot_address_compute_hash (t);
|
||
slot = htab_find_slot_with_hash (temp_slot_address_table, t, t->hash, INSERT);
|
||
*slot = t;
|
||
}
|
||
|
||
/* Remove an address -> temp slot mapping entry if the temp slot is
|
||
not in use anymore. Callback for remove_unused_temp_slot_addresses. */
|
||
static int
|
||
remove_unused_temp_slot_addresses_1 (void **slot, void *data ATTRIBUTE_UNUSED)
|
||
{
|
||
const struct temp_slot_address_entry *t;
|
||
t = (const struct temp_slot_address_entry *) *slot;
|
||
if (! t->temp_slot->in_use)
|
||
htab_clear_slot (temp_slot_address_table, slot);
|
||
return 1;
|
||
}
|
||
|
||
/* Remove all mappings of addresses to unused temp slots. */
|
||
static void
|
||
remove_unused_temp_slot_addresses (void)
|
||
{
|
||
/* Use quicker clearing if there aren't any active temp slots. */
|
||
if (n_temp_slots_in_use)
|
||
htab_traverse (temp_slot_address_table,
|
||
remove_unused_temp_slot_addresses_1,
|
||
NULL);
|
||
else
|
||
htab_empty (temp_slot_address_table);
|
||
}
|
||
|
||
/* Find the temp slot corresponding to the object at address X. */
|
||
|
||
static struct temp_slot *
|
||
find_temp_slot_from_address (rtx x)
|
||
{
|
||
struct temp_slot *p;
|
||
struct temp_slot_address_entry tmp, *t;
|
||
|
||
/* First try the easy way:
|
||
See if X exists in the address -> temp slot mapping. */
|
||
tmp.address = x;
|
||
tmp.temp_slot = NULL;
|
||
tmp.hash = temp_slot_address_compute_hash (&tmp);
|
||
t = (struct temp_slot_address_entry *)
|
||
htab_find_with_hash (temp_slot_address_table, &tmp, tmp.hash);
|
||
if (t)
|
||
return t->temp_slot;
|
||
|
||
/* If we have a sum involving a register, see if it points to a temp
|
||
slot. */
|
||
if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 0))
|
||
&& (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
|
||
return p;
|
||
else if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 1))
|
||
&& (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
|
||
return p;
|
||
|
||
/* Last resort: Address is a virtual stack var address. */
|
||
if (GET_CODE (x) == PLUS
|
||
&& XEXP (x, 0) == virtual_stack_vars_rtx
|
||
&& CONST_INT_P (XEXP (x, 1)))
|
||
{
|
||
int i;
|
||
for (i = max_slot_level (); i >= 0; i--)
|
||
for (p = *temp_slots_at_level (i); p; p = p->next)
|
||
{
|
||
if (INTVAL (XEXP (x, 1)) >= p->base_offset
|
||
&& INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size)
|
||
return p;
|
||
}
|
||
}
|
||
|
||
return NULL;
|
||
}
|
||
|
||
/* Allocate a temporary stack slot and record it for possible later
|
||
reuse.
|
||
|
||
MODE is the machine mode to be given to the returned rtx.
|
||
|
||
SIZE is the size in units of the space required. We do no rounding here
|
||
since assign_stack_local will do any required rounding.
|
||
|
||
TYPE is the type that will be used for the stack slot. */
|
||
|
||
rtx
|
||
assign_stack_temp_for_type (enum machine_mode mode, HOST_WIDE_INT size,
|
||
tree type)
|
||
{
|
||
unsigned int align;
|
||
struct temp_slot *p, *best_p = 0, *selected = NULL, **pp;
|
||
rtx slot;
|
||
|
||
/* If SIZE is -1 it means that somebody tried to allocate a temporary
|
||
of a variable size. */
|
||
gcc_assert (size != -1);
|
||
|
||
align = get_stack_local_alignment (type, mode);
|
||
|
||
/* Try to find an available, already-allocated temporary of the proper
|
||
mode which meets the size and alignment requirements. Choose the
|
||
smallest one with the closest alignment.
|
||
|
||
If assign_stack_temp is called outside of the tree->rtl expansion,
|
||
we cannot reuse the stack slots (that may still refer to
|
||
VIRTUAL_STACK_VARS_REGNUM). */
|
||
if (!virtuals_instantiated)
|
||
{
|
||
for (p = avail_temp_slots; p; p = p->next)
|
||
{
|
||
if (p->align >= align && p->size >= size
|
||
&& GET_MODE (p->slot) == mode
|
||
&& objects_must_conflict_p (p->type, type)
|
||
&& (best_p == 0 || best_p->size > p->size
|
||
|| (best_p->size == p->size && best_p->align > p->align)))
|
||
{
|
||
if (p->align == align && p->size == size)
|
||
{
|
||
selected = p;
|
||
cut_slot_from_list (selected, &avail_temp_slots);
|
||
best_p = 0;
|
||
break;
|
||
}
|
||
best_p = p;
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Make our best, if any, the one to use. */
|
||
if (best_p)
|
||
{
|
||
selected = best_p;
|
||
cut_slot_from_list (selected, &avail_temp_slots);
|
||
|
||
/* If there are enough aligned bytes left over, make them into a new
|
||
temp_slot so that the extra bytes don't get wasted. Do this only
|
||
for BLKmode slots, so that we can be sure of the alignment. */
|
||
if (GET_MODE (best_p->slot) == BLKmode)
|
||
{
|
||
int alignment = best_p->align / BITS_PER_UNIT;
|
||
HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
|
||
|
||
if (best_p->size - rounded_size >= alignment)
|
||
{
|
||
p = ggc_alloc_temp_slot ();
|
||
p->in_use = 0;
|
||
p->size = best_p->size - rounded_size;
|
||
p->base_offset = best_p->base_offset + rounded_size;
|
||
p->full_size = best_p->full_size - rounded_size;
|
||
p->slot = adjust_address_nv (best_p->slot, BLKmode, rounded_size);
|
||
p->align = best_p->align;
|
||
p->type = best_p->type;
|
||
insert_slot_to_list (p, &avail_temp_slots);
|
||
|
||
stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
|
||
stack_slot_list);
|
||
|
||
best_p->size = rounded_size;
|
||
best_p->full_size = rounded_size;
|
||
}
|
||
}
|
||
}
|
||
|
||
/* If we still didn't find one, make a new temporary. */
|
||
if (selected == 0)
|
||
{
|
||
HOST_WIDE_INT frame_offset_old = frame_offset;
|
||
|
||
p = ggc_alloc_temp_slot ();
|
||
|
||
/* We are passing an explicit alignment request to assign_stack_local.
|
||
One side effect of that is assign_stack_local will not round SIZE
|
||
to ensure the frame offset remains suitably aligned.
|
||
|
||
So for requests which depended on the rounding of SIZE, we go ahead
|
||
and round it now. We also make sure ALIGNMENT is at least
|
||
BIGGEST_ALIGNMENT. */
|
||
gcc_assert (mode != BLKmode || align == BIGGEST_ALIGNMENT);
|
||
p->slot = assign_stack_local_1 (mode,
|
||
(mode == BLKmode
|
||
? CEIL_ROUND (size,
|
||
(int) align
|
||
/ BITS_PER_UNIT)
|
||
: size),
|
||
align, 0);
|
||
|
||
p->align = align;
|
||
|
||
/* The following slot size computation is necessary because we don't
|
||
know the actual size of the temporary slot until assign_stack_local
|
||
has performed all the frame alignment and size rounding for the
|
||
requested temporary. Note that extra space added for alignment
|
||
can be either above or below this stack slot depending on which
|
||
way the frame grows. We include the extra space if and only if it
|
||
is above this slot. */
|
||
if (FRAME_GROWS_DOWNWARD)
|
||
p->size = frame_offset_old - frame_offset;
|
||
else
|
||
p->size = size;
|
||
|
||
/* Now define the fields used by combine_temp_slots. */
|
||
if (FRAME_GROWS_DOWNWARD)
|
||
{
|
||
p->base_offset = frame_offset;
|
||
p->full_size = frame_offset_old - frame_offset;
|
||
}
|
||
else
|
||
{
|
||
p->base_offset = frame_offset_old;
|
||
p->full_size = frame_offset - frame_offset_old;
|
||
}
|
||
|
||
selected = p;
|
||
}
|
||
|
||
p = selected;
|
||
p->in_use = 1;
|
||
p->type = type;
|
||
p->level = temp_slot_level;
|
||
n_temp_slots_in_use++;
|
||
|
||
pp = temp_slots_at_level (p->level);
|
||
insert_slot_to_list (p, pp);
|
||
insert_temp_slot_address (XEXP (p->slot, 0), p);
|
||
|
||
/* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
|
||
slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
|
||
stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
|
||
|
||
/* If we know the alias set for the memory that will be used, use
|
||
it. If there's no TYPE, then we don't know anything about the
|
||
alias set for the memory. */
|
||
set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
|
||
set_mem_align (slot, align);
|
||
|
||
/* If a type is specified, set the relevant flags. */
|
||
if (type != 0)
|
||
MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
|
||
MEM_NOTRAP_P (slot) = 1;
|
||
|
||
return slot;
|
||
}
|
||
|
||
/* Allocate a temporary stack slot and record it for possible later
|
||
reuse. First two arguments are same as in preceding function. */
|
||
|
||
rtx
|
||
assign_stack_temp (enum machine_mode mode, HOST_WIDE_INT size)
|
||
{
|
||
return assign_stack_temp_for_type (mode, size, NULL_TREE);
|
||
}
|
||
|
||
/* Assign a temporary.
|
||
If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
|
||
and so that should be used in error messages. In either case, we
|
||
allocate of the given type.
|
||
MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
|
||
it is 0 if a register is OK.
|
||
DONT_PROMOTE is 1 if we should not promote values in register
|
||
to wider modes. */
|
||
|
||
rtx
|
||
assign_temp (tree type_or_decl, int memory_required,
|
||
int dont_promote ATTRIBUTE_UNUSED)
|
||
{
|
||
tree type, decl;
|
||
enum machine_mode mode;
|
||
#ifdef PROMOTE_MODE
|
||
int unsignedp;
|
||
#endif
|
||
|
||
if (DECL_P (type_or_decl))
|
||
decl = type_or_decl, type = TREE_TYPE (decl);
|
||
else
|
||
decl = NULL, type = type_or_decl;
|
||
|
||
mode = TYPE_MODE (type);
|
||
#ifdef PROMOTE_MODE
|
||
unsignedp = TYPE_UNSIGNED (type);
|
||
#endif
|
||
|
||
if (mode == BLKmode || memory_required)
|
||
{
|
||
HOST_WIDE_INT size = int_size_in_bytes (type);
|
||
rtx tmp;
|
||
|
||
/* Zero sized arrays are GNU C extension. Set size to 1 to avoid
|
||
problems with allocating the stack space. */
|
||
if (size == 0)
|
||
size = 1;
|
||
|
||
/* Unfortunately, we don't yet know how to allocate variable-sized
|
||
temporaries. However, sometimes we can find a fixed upper limit on
|
||
the size, so try that instead. */
|
||
else if (size == -1)
|
||
size = max_int_size_in_bytes (type);
|
||
|
||
/* The size of the temporary may be too large to fit into an integer. */
|
||
/* ??? Not sure this should happen except for user silliness, so limit
|
||
this to things that aren't compiler-generated temporaries. The
|
||
rest of the time we'll die in assign_stack_temp_for_type. */
|
||
if (decl && size == -1
|
||
&& TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
|
||
{
|
||
error ("size of variable %q+D is too large", decl);
|
||
size = 1;
|
||
}
|
||
|
||
tmp = assign_stack_temp_for_type (mode, size, type);
|
||
return tmp;
|
||
}
|
||
|
||
#ifdef PROMOTE_MODE
|
||
if (! dont_promote)
|
||
mode = promote_mode (type, mode, &unsignedp);
|
||
#endif
|
||
|
||
return gen_reg_rtx (mode);
|
||
}
|
||
|
||
/* Combine temporary stack slots which are adjacent on the stack.
|
||
|
||
This allows for better use of already allocated stack space. This is only
|
||
done for BLKmode slots because we can be sure that we won't have alignment
|
||
problems in this case. */
|
||
|
||
static void
|
||
combine_temp_slots (void)
|
||
{
|
||
struct temp_slot *p, *q, *next, *next_q;
|
||
int num_slots;
|
||
|
||
/* We can't combine slots, because the information about which slot
|
||
is in which alias set will be lost. */
|
||
if (flag_strict_aliasing)
|
||
return;
|
||
|
||
/* If there are a lot of temp slots, don't do anything unless
|
||
high levels of optimization. */
|
||
if (! flag_expensive_optimizations)
|
||
for (p = avail_temp_slots, num_slots = 0; p; p = p->next, num_slots++)
|
||
if (num_slots > 100 || (num_slots > 10 && optimize == 0))
|
||
return;
|
||
|
||
for (p = avail_temp_slots; p; p = next)
|
||
{
|
||
int delete_p = 0;
|
||
|
||
next = p->next;
|
||
|
||
if (GET_MODE (p->slot) != BLKmode)
|
||
continue;
|
||
|
||
for (q = p->next; q; q = next_q)
|
||
{
|
||
int delete_q = 0;
|
||
|
||
next_q = q->next;
|
||
|
||
if (GET_MODE (q->slot) != BLKmode)
|
||
continue;
|
||
|
||
if (p->base_offset + p->full_size == q->base_offset)
|
||
{
|
||
/* Q comes after P; combine Q into P. */
|
||
p->size += q->size;
|
||
p->full_size += q->full_size;
|
||
delete_q = 1;
|
||
}
|
||
else if (q->base_offset + q->full_size == p->base_offset)
|
||
{
|
||
/* P comes after Q; combine P into Q. */
|
||
q->size += p->size;
|
||
q->full_size += p->full_size;
|
||
delete_p = 1;
|
||
break;
|
||
}
|
||
if (delete_q)
|
||
cut_slot_from_list (q, &avail_temp_slots);
|
||
}
|
||
|
||
/* Either delete P or advance past it. */
|
||
if (delete_p)
|
||
cut_slot_from_list (p, &avail_temp_slots);
|
||
}
|
||
}
|
||
|
||
/* Indicate that NEW_RTX is an alternate way of referring to the temp
|
||
slot that previously was known by OLD_RTX. */
|
||
|
||
void
|
||
update_temp_slot_address (rtx old_rtx, rtx new_rtx)
|
||
{
|
||
struct temp_slot *p;
|
||
|
||
if (rtx_equal_p (old_rtx, new_rtx))
|
||
return;
|
||
|
||
p = find_temp_slot_from_address (old_rtx);
|
||
|
||
/* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and
|
||
NEW_RTX is a register, see if one operand of the PLUS is a
|
||
temporary location. If so, NEW_RTX points into it. Otherwise,
|
||
if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
|
||
in common between them. If so, try a recursive call on those
|
||
values. */
|
||
if (p == 0)
|
||
{
|
||
if (GET_CODE (old_rtx) != PLUS)
|
||
return;
|
||
|
||
if (REG_P (new_rtx))
|
||
{
|
||
update_temp_slot_address (XEXP (old_rtx, 0), new_rtx);
|
||
update_temp_slot_address (XEXP (old_rtx, 1), new_rtx);
|
||
return;
|
||
}
|
||
else if (GET_CODE (new_rtx) != PLUS)
|
||
return;
|
||
|
||
if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 0)))
|
||
update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 1));
|
||
else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 0)))
|
||
update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 1));
|
||
else if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 1)))
|
||
update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 0));
|
||
else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 1)))
|
||
update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 0));
|
||
|
||
return;
|
||
}
|
||
|
||
/* Otherwise add an alias for the temp's address. */
|
||
insert_temp_slot_address (new_rtx, p);
|
||
}
|
||
|
||
/* If X could be a reference to a temporary slot, mark that slot as
|
||
belonging to the to one level higher than the current level. If X
|
||
matched one of our slots, just mark that one. Otherwise, we can't
|
||
easily predict which it is, so upgrade all of them.
|
||
|
||
This is called when an ({...}) construct occurs and a statement
|
||
returns a value in memory. */
|
||
|
||
void
|
||
preserve_temp_slots (rtx x)
|
||
{
|
||
struct temp_slot *p = 0, *next;
|
||
|
||
if (x == 0)
|
||
return;
|
||
|
||
/* If X is a register that is being used as a pointer, see if we have
|
||
a temporary slot we know it points to. */
|
||
if (REG_P (x) && REG_POINTER (x))
|
||
p = find_temp_slot_from_address (x);
|
||
|
||
/* If X is not in memory or is at a constant address, it cannot be in
|
||
a temporary slot. */
|
||
if (p == 0 && (!MEM_P (x) || CONSTANT_P (XEXP (x, 0))))
|
||
return;
|
||
|
||
/* First see if we can find a match. */
|
||
if (p == 0)
|
||
p = find_temp_slot_from_address (XEXP (x, 0));
|
||
|
||
if (p != 0)
|
||
{
|
||
if (p->level == temp_slot_level)
|
||
move_slot_to_level (p, temp_slot_level - 1);
|
||
return;
|
||
}
|
||
|
||
/* Otherwise, preserve all non-kept slots at this level. */
|
||
for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
|
||
{
|
||
next = p->next;
|
||
move_slot_to_level (p, temp_slot_level - 1);
|
||
}
|
||
}
|
||
|
||
/* Free all temporaries used so far. This is normally called at the
|
||
end of generating code for a statement. */
|
||
|
||
void
|
||
free_temp_slots (void)
|
||
{
|
||
struct temp_slot *p, *next;
|
||
bool some_available = false;
|
||
|
||
for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
|
||
{
|
||
next = p->next;
|
||
make_slot_available (p);
|
||
some_available = true;
|
||
}
|
||
|
||
if (some_available)
|
||
{
|
||
remove_unused_temp_slot_addresses ();
|
||
combine_temp_slots ();
|
||
}
|
||
}
|
||
|
||
/* Push deeper into the nesting level for stack temporaries. */
|
||
|
||
void
|
||
push_temp_slots (void)
|
||
{
|
||
temp_slot_level++;
|
||
}
|
||
|
||
/* Pop a temporary nesting level. All slots in use in the current level
|
||
are freed. */
|
||
|
||
void
|
||
pop_temp_slots (void)
|
||
{
|
||
free_temp_slots ();
|
||
temp_slot_level--;
|
||
}
|
||
|
||
/* Initialize temporary slots. */
|
||
|
||
void
|
||
init_temp_slots (void)
|
||
{
|
||
/* We have not allocated any temporaries yet. */
|
||
avail_temp_slots = 0;
|
||
used_temp_slots = 0;
|
||
temp_slot_level = 0;
|
||
n_temp_slots_in_use = 0;
|
||
|
||
/* Set up the table to map addresses to temp slots. */
|
||
if (! temp_slot_address_table)
|
||
temp_slot_address_table = htab_create_ggc (32,
|
||
temp_slot_address_hash,
|
||
temp_slot_address_eq,
|
||
NULL);
|
||
else
|
||
htab_empty (temp_slot_address_table);
|
||
}
|
||
|
||
/* Functions and data structures to keep track of the values hard regs
|
||
had at the start of the function. */
|
||
|
||
/* Private type used by get_hard_reg_initial_reg, get_hard_reg_initial_val,
|
||
and has_hard_reg_initial_val.. */
|
||
typedef struct GTY(()) initial_value_pair {
|
||
rtx hard_reg;
|
||
rtx pseudo;
|
||
} initial_value_pair;
|
||
/* ??? This could be a VEC but there is currently no way to define an
|
||
opaque VEC type. This could be worked around by defining struct
|
||
initial_value_pair in function.h. */
|
||
typedef struct GTY(()) initial_value_struct {
|
||
int num_entries;
|
||
int max_entries;
|
||
initial_value_pair * GTY ((length ("%h.num_entries"))) entries;
|
||
} initial_value_struct;
|
||
|
||
/* If a pseudo represents an initial hard reg (or expression), return
|
||
it, else return NULL_RTX. */
|
||
|
||
rtx
|
||
get_hard_reg_initial_reg (rtx reg)
|
||
{
|
||
struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
|
||
int i;
|
||
|
||
if (ivs == 0)
|
||
return NULL_RTX;
|
||
|
||
for (i = 0; i < ivs->num_entries; i++)
|
||
if (rtx_equal_p (ivs->entries[i].pseudo, reg))
|
||
return ivs->entries[i].hard_reg;
|
||
|
||
return NULL_RTX;
|
||
}
|
||
|
||
/* Make sure that there's a pseudo register of mode MODE that stores the
|
||
initial value of hard register REGNO. Return an rtx for such a pseudo. */
|
||
|
||
rtx
|
||
get_hard_reg_initial_val (enum machine_mode mode, unsigned int regno)
|
||
{
|
||
struct initial_value_struct *ivs;
|
||
rtx rv;
|
||
|
||
rv = has_hard_reg_initial_val (mode, regno);
|
||
if (rv)
|
||
return rv;
|
||
|
||
ivs = crtl->hard_reg_initial_vals;
|
||
if (ivs == 0)
|
||
{
|
||
ivs = ggc_alloc_initial_value_struct ();
|
||
ivs->num_entries = 0;
|
||
ivs->max_entries = 5;
|
||
ivs->entries = ggc_alloc_vec_initial_value_pair (5);
|
||
crtl->hard_reg_initial_vals = ivs;
|
||
}
|
||
|
||
if (ivs->num_entries >= ivs->max_entries)
|
||
{
|
||
ivs->max_entries += 5;
|
||
ivs->entries = GGC_RESIZEVEC (initial_value_pair, ivs->entries,
|
||
ivs->max_entries);
|
||
}
|
||
|
||
ivs->entries[ivs->num_entries].hard_reg = gen_rtx_REG (mode, regno);
|
||
ivs->entries[ivs->num_entries].pseudo = gen_reg_rtx (mode);
|
||
|
||
return ivs->entries[ivs->num_entries++].pseudo;
|
||
}
|
||
|
||
/* See if get_hard_reg_initial_val has been used to create a pseudo
|
||
for the initial value of hard register REGNO in mode MODE. Return
|
||
the associated pseudo if so, otherwise return NULL. */
|
||
|
||
rtx
|
||
has_hard_reg_initial_val (enum machine_mode mode, unsigned int regno)
|
||
{
|
||
struct initial_value_struct *ivs;
|
||
int i;
|
||
|
||
ivs = crtl->hard_reg_initial_vals;
|
||
if (ivs != 0)
|
||
for (i = 0; i < ivs->num_entries; i++)
|
||
if (GET_MODE (ivs->entries[i].hard_reg) == mode
|
||
&& REGNO (ivs->entries[i].hard_reg) == regno)
|
||
return ivs->entries[i].pseudo;
|
||
|
||
return NULL_RTX;
|
||
}
|
||
|
||
unsigned int
|
||
emit_initial_value_sets (void)
|
||
{
|
||
struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
|
||
int i;
|
||
rtx seq;
|
||
|
||
if (ivs == 0)
|
||
return 0;
|
||
|
||
start_sequence ();
|
||
for (i = 0; i < ivs->num_entries; i++)
|
||
emit_move_insn (ivs->entries[i].pseudo, ivs->entries[i].hard_reg);
|
||
seq = get_insns ();
|
||
end_sequence ();
|
||
|
||
emit_insn_at_entry (seq);
|
||
return 0;
|
||
}
|
||
|
||
/* Return the hardreg-pseudoreg initial values pair entry I and
|
||
TRUE if I is a valid entry, or FALSE if I is not a valid entry. */
|
||
bool
|
||
initial_value_entry (int i, rtx *hreg, rtx *preg)
|
||
{
|
||
struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
|
||
if (!ivs || i >= ivs->num_entries)
|
||
return false;
|
||
|
||
*hreg = ivs->entries[i].hard_reg;
|
||
*preg = ivs->entries[i].pseudo;
|
||
return true;
|
||
}
|
||
|
||
/* These routines are responsible for converting virtual register references
|
||
to the actual hard register references once RTL generation is complete.
|
||
|
||
The following four variables are used for communication between the
|
||
routines. They contain the offsets of the virtual registers from their
|
||
respective hard registers. */
|
||
|
||
static int in_arg_offset;
|
||
static int var_offset;
|
||
static int dynamic_offset;
|
||
static int out_arg_offset;
|
||
static int cfa_offset;
|
||
|
||
/* In most machines, the stack pointer register is equivalent to the bottom
|
||
of the stack. */
|
||
|
||
#ifndef STACK_POINTER_OFFSET
|
||
#define STACK_POINTER_OFFSET 0
|
||
#endif
|
||
|
||
/* If not defined, pick an appropriate default for the offset of dynamically
|
||
allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
|
||
REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
|
||
|
||
#ifndef STACK_DYNAMIC_OFFSET
|
||
|
||
/* The bottom of the stack points to the actual arguments. If
|
||
REG_PARM_STACK_SPACE is defined, this includes the space for the register
|
||
parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
|
||
stack space for register parameters is not pushed by the caller, but
|
||
rather part of the fixed stack areas and hence not included in
|
||
`crtl->outgoing_args_size'. Nevertheless, we must allow
|
||
for it when allocating stack dynamic objects. */
|
||
|
||
#if defined(REG_PARM_STACK_SPACE)
|
||
#define STACK_DYNAMIC_OFFSET(FNDECL) \
|
||
((ACCUMULATE_OUTGOING_ARGS \
|
||
? (crtl->outgoing_args_size \
|
||
+ (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
|
||
: REG_PARM_STACK_SPACE (FNDECL))) \
|
||
: 0) + (STACK_POINTER_OFFSET))
|
||
#else
|
||
#define STACK_DYNAMIC_OFFSET(FNDECL) \
|
||
((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : 0) \
|
||
+ (STACK_POINTER_OFFSET))
|
||
#endif
|
||
#endif
|
||
|
||
|
||
/* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
|
||
is a virtual register, return the equivalent hard register and set the
|
||
offset indirectly through the pointer. Otherwise, return 0. */
|
||
|
||
static rtx
|
||
instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset)
|
||
{
|
||
rtx new_rtx;
|
||
HOST_WIDE_INT offset;
|
||
|
||
if (x == virtual_incoming_args_rtx)
|
||
{
|
||
if (stack_realign_drap)
|
||
{
|
||
/* Replace virtual_incoming_args_rtx with internal arg
|
||
pointer if DRAP is used to realign stack. */
|
||
new_rtx = crtl->args.internal_arg_pointer;
|
||
offset = 0;
|
||
}
|
||
else
|
||
new_rtx = arg_pointer_rtx, offset = in_arg_offset;
|
||
}
|
||
else if (x == virtual_stack_vars_rtx)
|
||
new_rtx = frame_pointer_rtx, offset = var_offset;
|
||
else if (x == virtual_stack_dynamic_rtx)
|
||
new_rtx = stack_pointer_rtx, offset = dynamic_offset;
|
||
else if (x == virtual_outgoing_args_rtx)
|
||
new_rtx = stack_pointer_rtx, offset = out_arg_offset;
|
||
else if (x == virtual_cfa_rtx)
|
||
{
|
||
#ifdef FRAME_POINTER_CFA_OFFSET
|
||
new_rtx = frame_pointer_rtx;
|
||
#else
|
||
new_rtx = arg_pointer_rtx;
|
||
#endif
|
||
offset = cfa_offset;
|
||
}
|
||
else if (x == virtual_preferred_stack_boundary_rtx)
|
||
{
|
||
new_rtx = GEN_INT (crtl->preferred_stack_boundary / BITS_PER_UNIT);
|
||
offset = 0;
|
||
}
|
||
else
|
||
return NULL_RTX;
|
||
|
||
*poffset = offset;
|
||
return new_rtx;
|
||
}
|
||
|
||
/* A subroutine of instantiate_virtual_regs, called via for_each_rtx.
|
||
Instantiate any virtual registers present inside of *LOC. The expression
|
||
is simplified, as much as possible, but is not to be considered "valid"
|
||
in any sense implied by the target. If any change is made, set CHANGED
|
||
to true. */
|
||
|
||
static int
|
||
instantiate_virtual_regs_in_rtx (rtx *loc, void *data)
|
||
{
|
||
HOST_WIDE_INT offset;
|
||
bool *changed = (bool *) data;
|
||
rtx x, new_rtx;
|
||
|
||
x = *loc;
|
||
if (x == 0)
|
||
return 0;
|
||
|
||
switch (GET_CODE (x))
|
||
{
|
||
case REG:
|
||
new_rtx = instantiate_new_reg (x, &offset);
|
||
if (new_rtx)
|
||
{
|
||
*loc = plus_constant (GET_MODE (x), new_rtx, offset);
|
||
if (changed)
|
||
*changed = true;
|
||
}
|
||
return -1;
|
||
|
||
case PLUS:
|
||
new_rtx = instantiate_new_reg (XEXP (x, 0), &offset);
|
||
if (new_rtx)
|
||
{
|
||
new_rtx = plus_constant (GET_MODE (x), new_rtx, offset);
|
||
*loc = simplify_gen_binary (PLUS, GET_MODE (x), new_rtx, XEXP (x, 1));
|
||
if (changed)
|
||
*changed = true;
|
||
return -1;
|
||
}
|
||
|
||
/* FIXME -- from old code */
|
||
/* If we have (plus (subreg (virtual-reg)) (const_int)), we know
|
||
we can commute the PLUS and SUBREG because pointers into the
|
||
frame are well-behaved. */
|
||
break;
|
||
|
||
default:
|
||
break;
|
||
}
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
|
||
matches the predicate for insn CODE operand OPERAND. */
|
||
|
||
static int
|
||
safe_insn_predicate (int code, int operand, rtx x)
|
||
{
|
||
return code < 0 || insn_operand_matches ((enum insn_code) code, operand, x);
|
||
}
|
||
|
||
/* A subroutine of instantiate_virtual_regs. Instantiate any virtual
|
||
registers present inside of insn. The result will be a valid insn. */
|
||
|
||
static void
|
||
instantiate_virtual_regs_in_insn (rtx insn)
|
||
{
|
||
HOST_WIDE_INT offset;
|
||
int insn_code, i;
|
||
bool any_change = false;
|
||
rtx set, new_rtx, x, seq;
|
||
|
||
/* There are some special cases to be handled first. */
|
||
set = single_set (insn);
|
||
if (set)
|
||
{
|
||
/* We're allowed to assign to a virtual register. This is interpreted
|
||
to mean that the underlying register gets assigned the inverse
|
||
transformation. This is used, for example, in the handling of
|
||
non-local gotos. */
|
||
new_rtx = instantiate_new_reg (SET_DEST (set), &offset);
|
||
if (new_rtx)
|
||
{
|
||
start_sequence ();
|
||
|
||
for_each_rtx (&SET_SRC (set), instantiate_virtual_regs_in_rtx, NULL);
|
||
x = simplify_gen_binary (PLUS, GET_MODE (new_rtx), SET_SRC (set),
|
||
GEN_INT (-offset));
|
||
x = force_operand (x, new_rtx);
|
||
if (x != new_rtx)
|
||
emit_move_insn (new_rtx, x);
|
||
|
||
seq = get_insns ();
|
||
end_sequence ();
|
||
|
||
emit_insn_before (seq, insn);
|
||
delete_insn (insn);
|
||
return;
|
||
}
|
||
|
||
/* Handle a straight copy from a virtual register by generating a
|
||
new add insn. The difference between this and falling through
|
||
to the generic case is avoiding a new pseudo and eliminating a
|
||
move insn in the initial rtl stream. */
|
||
new_rtx = instantiate_new_reg (SET_SRC (set), &offset);
|
||
if (new_rtx && offset != 0
|
||
&& REG_P (SET_DEST (set))
|
||
&& REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
|
||
{
|
||
start_sequence ();
|
||
|
||
x = expand_simple_binop (GET_MODE (SET_DEST (set)), PLUS,
|
||
new_rtx, GEN_INT (offset), SET_DEST (set),
|
||
1, OPTAB_LIB_WIDEN);
|
||
if (x != SET_DEST (set))
|
||
emit_move_insn (SET_DEST (set), x);
|
||
|
||
seq = get_insns ();
|
||
end_sequence ();
|
||
|
||
emit_insn_before (seq, insn);
|
||
delete_insn (insn);
|
||
return;
|
||
}
|
||
|
||
extract_insn (insn);
|
||
insn_code = INSN_CODE (insn);
|
||
|
||
/* Handle a plus involving a virtual register by determining if the
|
||
operands remain valid if they're modified in place. */
|
||
if (GET_CODE (SET_SRC (set)) == PLUS
|
||
&& recog_data.n_operands >= 3
|
||
&& recog_data.operand_loc[1] == &XEXP (SET_SRC (set), 0)
|
||
&& recog_data.operand_loc[2] == &XEXP (SET_SRC (set), 1)
|
||
&& CONST_INT_P (recog_data.operand[2])
|
||
&& (new_rtx = instantiate_new_reg (recog_data.operand[1], &offset)))
|
||
{
|
||
offset += INTVAL (recog_data.operand[2]);
|
||
|
||
/* If the sum is zero, then replace with a plain move. */
|
||
if (offset == 0
|
||
&& REG_P (SET_DEST (set))
|
||
&& REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
|
||
{
|
||
start_sequence ();
|
||
emit_move_insn (SET_DEST (set), new_rtx);
|
||
seq = get_insns ();
|
||
end_sequence ();
|
||
|
||
emit_insn_before (seq, insn);
|
||
delete_insn (insn);
|
||
return;
|
||
}
|
||
|
||
x = gen_int_mode (offset, recog_data.operand_mode[2]);
|
||
|
||
/* Using validate_change and apply_change_group here leaves
|
||
recog_data in an invalid state. Since we know exactly what
|
||
we want to check, do those two by hand. */
|
||
if (safe_insn_predicate (insn_code, 1, new_rtx)
|
||
&& safe_insn_predicate (insn_code, 2, x))
|
||
{
|
||
*recog_data.operand_loc[1] = recog_data.operand[1] = new_rtx;
|
||
*recog_data.operand_loc[2] = recog_data.operand[2] = x;
|
||
any_change = true;
|
||
|
||
/* Fall through into the regular operand fixup loop in
|
||
order to take care of operands other than 1 and 2. */
|
||
}
|
||
}
|
||
}
|
||
else
|
||
{
|
||
extract_insn (insn);
|
||
insn_code = INSN_CODE (insn);
|
||
}
|
||
|
||
/* In the general case, we expect virtual registers to appear only in
|
||
operands, and then only as either bare registers or inside memories. */
|
||
for (i = 0; i < recog_data.n_operands; ++i)
|
||
{
|
||
x = recog_data.operand[i];
|
||
switch (GET_CODE (x))
|
||
{
|
||
case MEM:
|
||
{
|
||
rtx addr = XEXP (x, 0);
|
||
bool changed = false;
|
||
|
||
for_each_rtx (&addr, instantiate_virtual_regs_in_rtx, &changed);
|
||
if (!changed)
|
||
continue;
|
||
|
||
start_sequence ();
|
||
x = replace_equiv_address (x, addr);
|
||
/* It may happen that the address with the virtual reg
|
||
was valid (e.g. based on the virtual stack reg, which might
|
||
be acceptable to the predicates with all offsets), whereas
|
||
the address now isn't anymore, for instance when the address
|
||
is still offsetted, but the base reg isn't virtual-stack-reg
|
||
anymore. Below we would do a force_reg on the whole operand,
|
||
but this insn might actually only accept memory. Hence,
|
||
before doing that last resort, try to reload the address into
|
||
a register, so this operand stays a MEM. */
|
||
if (!safe_insn_predicate (insn_code, i, x))
|
||
{
|
||
addr = force_reg (GET_MODE (addr), addr);
|
||
x = replace_equiv_address (x, addr);
|
||
}
|
||
seq = get_insns ();
|
||
end_sequence ();
|
||
if (seq)
|
||
emit_insn_before (seq, insn);
|
||
}
|
||
break;
|
||
|
||
case REG:
|
||
new_rtx = instantiate_new_reg (x, &offset);
|
||
if (new_rtx == NULL)
|
||
continue;
|
||
if (offset == 0)
|
||
x = new_rtx;
|
||
else
|
||
{
|
||
start_sequence ();
|
||
|
||
/* Careful, special mode predicates may have stuff in
|
||
insn_data[insn_code].operand[i].mode that isn't useful
|
||
to us for computing a new value. */
|
||
/* ??? Recognize address_operand and/or "p" constraints
|
||
to see if (plus new offset) is a valid before we put
|
||
this through expand_simple_binop. */
|
||
x = expand_simple_binop (GET_MODE (x), PLUS, new_rtx,
|
||
GEN_INT (offset), NULL_RTX,
|
||
1, OPTAB_LIB_WIDEN);
|
||
seq = get_insns ();
|
||
end_sequence ();
|
||
emit_insn_before (seq, insn);
|
||
}
|
||
break;
|
||
|
||
case SUBREG:
|
||
new_rtx = instantiate_new_reg (SUBREG_REG (x), &offset);
|
||
if (new_rtx == NULL)
|
||
continue;
|
||
if (offset != 0)
|
||
{
|
||
start_sequence ();
|
||
new_rtx = expand_simple_binop (GET_MODE (new_rtx), PLUS, new_rtx,
|
||
GEN_INT (offset), NULL_RTX,
|
||
1, OPTAB_LIB_WIDEN);
|
||
seq = get_insns ();
|
||
end_sequence ();
|
||
emit_insn_before (seq, insn);
|
||
}
|
||
x = simplify_gen_subreg (recog_data.operand_mode[i], new_rtx,
|
||
GET_MODE (new_rtx), SUBREG_BYTE (x));
|
||
gcc_assert (x);
|
||
break;
|
||
|
||
default:
|
||
continue;
|
||
}
|
||
|
||
/* At this point, X contains the new value for the operand.
|
||
Validate the new value vs the insn predicate. Note that
|
||
asm insns will have insn_code -1 here. */
|
||
if (!safe_insn_predicate (insn_code, i, x))
|
||
{
|
||
start_sequence ();
|
||
if (REG_P (x))
|
||
{
|
||
gcc_assert (REGNO (x) <= LAST_VIRTUAL_REGISTER);
|
||
x = copy_to_reg (x);
|
||
}
|
||
else
|
||
x = force_reg (insn_data[insn_code].operand[i].mode, x);
|
||
seq = get_insns ();
|
||
end_sequence ();
|
||
if (seq)
|
||
emit_insn_before (seq, insn);
|
||
}
|
||
|
||
*recog_data.operand_loc[i] = recog_data.operand[i] = x;
|
||
any_change = true;
|
||
}
|
||
|
||
if (any_change)
|
||
{
|
||
/* Propagate operand changes into the duplicates. */
|
||
for (i = 0; i < recog_data.n_dups; ++i)
|
||
*recog_data.dup_loc[i]
|
||
= copy_rtx (recog_data.operand[(unsigned)recog_data.dup_num[i]]);
|
||
|
||
/* Force re-recognition of the instruction for validation. */
|
||
INSN_CODE (insn) = -1;
|
||
}
|
||
|
||
if (asm_noperands (PATTERN (insn)) >= 0)
|
||
{
|
||
if (!check_asm_operands (PATTERN (insn)))
|
||
{
|
||
error_for_asm (insn, "impossible constraint in %<asm%>");
|
||
delete_insn_and_edges (insn);
|
||
}
|
||
}
|
||
else
|
||
{
|
||
if (recog_memoized (insn) < 0)
|
||
fatal_insn_not_found (insn);
|
||
}
|
||
}
|
||
|
||
/* Subroutine of instantiate_decls. Given RTL representing a decl,
|
||
do any instantiation required. */
|
||
|
||
void
|
||
instantiate_decl_rtl (rtx x)
|
||
{
|
||
rtx addr;
|
||
|
||
if (x == 0)
|
||
return;
|
||
|
||
/* If this is a CONCAT, recurse for the pieces. */
|
||
if (GET_CODE (x) == CONCAT)
|
||
{
|
||
instantiate_decl_rtl (XEXP (x, 0));
|
||
instantiate_decl_rtl (XEXP (x, 1));
|
||
return;
|
||
}
|
||
|
||
/* If this is not a MEM, no need to do anything. Similarly if the
|
||
address is a constant or a register that is not a virtual register. */
|
||
if (!MEM_P (x))
|
||
return;
|
||
|
||
addr = XEXP (x, 0);
|
||
if (CONSTANT_P (addr)
|
||
|| (REG_P (addr)
|
||
&& (REGNO (addr) < FIRST_VIRTUAL_REGISTER
|
||
|| REGNO (addr) > LAST_VIRTUAL_REGISTER)))
|
||
return;
|
||
|
||
for_each_rtx (&XEXP (x, 0), instantiate_virtual_regs_in_rtx, NULL);
|
||
}
|
||
|
||
/* Helper for instantiate_decls called via walk_tree: Process all decls
|
||
in the given DECL_VALUE_EXPR. */
|
||
|
||
static tree
|
||
instantiate_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
|
||
{
|
||
tree t = *tp;
|
||
if (! EXPR_P (t))
|
||
{
|
||
*walk_subtrees = 0;
|
||
if (DECL_P (t))
|
||
{
|
||
if (DECL_RTL_SET_P (t))
|
||
instantiate_decl_rtl (DECL_RTL (t));
|
||
if (TREE_CODE (t) == PARM_DECL && DECL_NAMELESS (t)
|
||
&& DECL_INCOMING_RTL (t))
|
||
instantiate_decl_rtl (DECL_INCOMING_RTL (t));
|
||
if ((TREE_CODE (t) == VAR_DECL
|
||
|| TREE_CODE (t) == RESULT_DECL)
|
||
&& DECL_HAS_VALUE_EXPR_P (t))
|
||
{
|
||
tree v = DECL_VALUE_EXPR (t);
|
||
walk_tree (&v, instantiate_expr, NULL, NULL);
|
||
}
|
||
}
|
||
}
|
||
return NULL;
|
||
}
|
||
|
||
/* Subroutine of instantiate_decls: Process all decls in the given
|
||
BLOCK node and all its subblocks. */
|
||
|
||
static void
|
||
instantiate_decls_1 (tree let)
|
||
{
|
||
tree t;
|
||
|
||
for (t = BLOCK_VARS (let); t; t = DECL_CHAIN (t))
|
||
{
|
||
if (DECL_RTL_SET_P (t))
|
||
instantiate_decl_rtl (DECL_RTL (t));
|
||
if (TREE_CODE (t) == VAR_DECL && DECL_HAS_VALUE_EXPR_P (t))
|
||
{
|
||
tree v = DECL_VALUE_EXPR (t);
|
||
walk_tree (&v, instantiate_expr, NULL, NULL);
|
||
}
|
||
}
|
||
|
||
/* Process all subblocks. */
|
||
for (t = BLOCK_SUBBLOCKS (let); t; t = BLOCK_CHAIN (t))
|
||
instantiate_decls_1 (t);
|
||
}
|
||
|
||
/* Scan all decls in FNDECL (both variables and parameters) and instantiate
|
||
all virtual registers in their DECL_RTL's. */
|
||
|
||
static void
|
||
instantiate_decls (tree fndecl)
|
||
{
|
||
tree decl;
|
||
unsigned ix;
|
||
|
||
/* Process all parameters of the function. */
|
||
for (decl = DECL_ARGUMENTS (fndecl); decl; decl = DECL_CHAIN (decl))
|
||
{
|
||
instantiate_decl_rtl (DECL_RTL (decl));
|
||
instantiate_decl_rtl (DECL_INCOMING_RTL (decl));
|
||
if (DECL_HAS_VALUE_EXPR_P (decl))
|
||
{
|
||
tree v = DECL_VALUE_EXPR (decl);
|
||
walk_tree (&v, instantiate_expr, NULL, NULL);
|
||
}
|
||
}
|
||
|
||
if ((decl = DECL_RESULT (fndecl))
|
||
&& TREE_CODE (decl) == RESULT_DECL)
|
||
{
|
||
if (DECL_RTL_SET_P (decl))
|
||
instantiate_decl_rtl (DECL_RTL (decl));
|
||
if (DECL_HAS_VALUE_EXPR_P (decl))
|
||
{
|
||
tree v = DECL_VALUE_EXPR (decl);
|
||
walk_tree (&v, instantiate_expr, NULL, NULL);
|
||
}
|
||
}
|
||
|
||
/* Now process all variables defined in the function or its subblocks. */
|
||
instantiate_decls_1 (DECL_INITIAL (fndecl));
|
||
|
||
FOR_EACH_LOCAL_DECL (cfun, ix, decl)
|
||
if (DECL_RTL_SET_P (decl))
|
||
instantiate_decl_rtl (DECL_RTL (decl));
|
||
VEC_free (tree, gc, cfun->local_decls);
|
||
}
|
||
|
||
/* Pass through the INSNS of function FNDECL and convert virtual register
|
||
references to hard register references. */
|
||
|
||
static unsigned int
|
||
instantiate_virtual_regs (void)
|
||
{
|
||
rtx insn;
|
||
|
||
/* Compute the offsets to use for this function. */
|
||
in_arg_offset = FIRST_PARM_OFFSET (current_function_decl);
|
||
var_offset = STARTING_FRAME_OFFSET;
|
||
dynamic_offset = STACK_DYNAMIC_OFFSET (current_function_decl);
|
||
out_arg_offset = STACK_POINTER_OFFSET;
|
||
#ifdef FRAME_POINTER_CFA_OFFSET
|
||
cfa_offset = FRAME_POINTER_CFA_OFFSET (current_function_decl);
|
||
#else
|
||
cfa_offset = ARG_POINTER_CFA_OFFSET (current_function_decl);
|
||
#endif
|
||
|
||
/* Initialize recognition, indicating that volatile is OK. */
|
||
init_recog ();
|
||
|
||
/* Scan through all the insns, instantiating every virtual register still
|
||
present. */
|
||
for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
|
||
if (INSN_P (insn))
|
||
{
|
||
/* These patterns in the instruction stream can never be recognized.
|
||
Fortunately, they shouldn't contain virtual registers either. */
|
||
if (GET_CODE (PATTERN (insn)) == USE
|
||
|| GET_CODE (PATTERN (insn)) == CLOBBER
|
||
|| GET_CODE (PATTERN (insn)) == ADDR_VEC
|
||
|| GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC
|
||
|| GET_CODE (PATTERN (insn)) == ASM_INPUT)
|
||
continue;
|
||
else if (DEBUG_INSN_P (insn))
|
||
for_each_rtx (&INSN_VAR_LOCATION (insn),
|
||
instantiate_virtual_regs_in_rtx, NULL);
|
||
else
|
||
instantiate_virtual_regs_in_insn (insn);
|
||
|
||
if (INSN_DELETED_P (insn))
|
||
continue;
|
||
|
||
for_each_rtx (®_NOTES (insn), instantiate_virtual_regs_in_rtx, NULL);
|
||
|
||
/* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
|
||
if (CALL_P (insn))
|
||
for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn),
|
||
instantiate_virtual_regs_in_rtx, NULL);
|
||
}
|
||
|
||
/* Instantiate the virtual registers in the DECLs for debugging purposes. */
|
||
instantiate_decls (current_function_decl);
|
||
|
||
targetm.instantiate_decls ();
|
||
|
||
/* Indicate that, from now on, assign_stack_local should use
|
||
frame_pointer_rtx. */
|
||
virtuals_instantiated = 1;
|
||
|
||
return 0;
|
||
}
|
||
|
||
struct rtl_opt_pass pass_instantiate_virtual_regs =
|
||
{
|
||
{
|
||
RTL_PASS,
|
||
"vregs", /* name */
|
||
NULL, /* gate */
|
||
instantiate_virtual_regs, /* execute */
|
||
NULL, /* sub */
|
||
NULL, /* next */
|
||
0, /* static_pass_number */
|
||
TV_NONE, /* tv_id */
|
||
0, /* properties_required */
|
||
0, /* properties_provided */
|
||
0, /* properties_destroyed */
|
||
0, /* todo_flags_start */
|
||
0 /* todo_flags_finish */
|
||
}
|
||
};
|
||
|
||
|
||
/* Return 1 if EXP is an aggregate type (or a value with aggregate type).
|
||
This means a type for which function calls must pass an address to the
|
||
function or get an address back from the function.
|
||
EXP may be a type node or an expression (whose type is tested). */
|
||
|
||
int
|
||
aggregate_value_p (const_tree exp, const_tree fntype)
|
||
{
|
||
const_tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
|
||
int i, regno, nregs;
|
||
rtx reg;
|
||
|
||
if (fntype)
|
||
switch (TREE_CODE (fntype))
|
||
{
|
||
case CALL_EXPR:
|
||
{
|
||
tree fndecl = get_callee_fndecl (fntype);
|
||
fntype = (fndecl
|
||
? TREE_TYPE (fndecl)
|
||
: TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (fntype))));
|
||
}
|
||
break;
|
||
case FUNCTION_DECL:
|
||
fntype = TREE_TYPE (fntype);
|
||
break;
|
||
case FUNCTION_TYPE:
|
||
case METHOD_TYPE:
|
||
break;
|
||
case IDENTIFIER_NODE:
|
||
fntype = NULL_TREE;
|
||
break;
|
||
default:
|
||
/* We don't expect other tree types here. */
|
||
gcc_unreachable ();
|
||
}
|
||
|
||
if (VOID_TYPE_P (type))
|
||
return 0;
|
||
|
||
/* If a record should be passed the same as its first (and only) member
|
||
don't pass it as an aggregate. */
|
||
if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
|
||
return aggregate_value_p (first_field (type), fntype);
|
||
|
||
/* If the front end has decided that this needs to be passed by
|
||
reference, do so. */
|
||
if ((TREE_CODE (exp) == PARM_DECL || TREE_CODE (exp) == RESULT_DECL)
|
||
&& DECL_BY_REFERENCE (exp))
|
||
return 1;
|
||
|
||
/* Function types that are TREE_ADDRESSABLE force return in memory. */
|
||
if (fntype && TREE_ADDRESSABLE (fntype))
|
||
return 1;
|
||
|
||
/* Types that are TREE_ADDRESSABLE must be constructed in memory,
|
||
and thus can't be returned in registers. */
|
||
if (TREE_ADDRESSABLE (type))
|
||
return 1;
|
||
|
||
if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
|
||
return 1;
|
||
|
||
if (targetm.calls.return_in_memory (type, fntype))
|
||
return 1;
|
||
|
||
/* Make sure we have suitable call-clobbered regs to return
|
||
the value in; if not, we must return it in memory. */
|
||
reg = hard_function_value (type, 0, fntype, 0);
|
||
|
||
/* If we have something other than a REG (e.g. a PARALLEL), then assume
|
||
it is OK. */
|
||
if (!REG_P (reg))
|
||
return 0;
|
||
|
||
regno = REGNO (reg);
|
||
nregs = hard_regno_nregs[regno][TYPE_MODE (type)];
|
||
for (i = 0; i < nregs; i++)
|
||
if (! call_used_regs[regno + i])
|
||
return 1;
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* Return true if we should assign DECL a pseudo register; false if it
|
||
should live on the local stack. */
|
||
|
||
bool
|
||
use_register_for_decl (const_tree decl)
|
||
{
|
||
if (!targetm.calls.allocate_stack_slots_for_args())
|
||
return true;
|
||
|
||
/* Honor volatile. */
|
||
if (TREE_SIDE_EFFECTS (decl))
|
||
return false;
|
||
|
||
/* Honor addressability. */
|
||
if (TREE_ADDRESSABLE (decl))
|
||
return false;
|
||
|
||
/* Only register-like things go in registers. */
|
||
if (DECL_MODE (decl) == BLKmode)
|
||
return false;
|
||
|
||
/* If -ffloat-store specified, don't put explicit float variables
|
||
into registers. */
|
||
/* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
|
||
propagates values across these stores, and it probably shouldn't. */
|
||
if (flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)))
|
||
return false;
|
||
|
||
/* If we're not interested in tracking debugging information for
|
||
this decl, then we can certainly put it in a register. */
|
||
if (DECL_IGNORED_P (decl))
|
||
return true;
|
||
|
||
if (optimize)
|
||
return true;
|
||
|
||
if (!DECL_REGISTER (decl))
|
||
return false;
|
||
|
||
switch (TREE_CODE (TREE_TYPE (decl)))
|
||
{
|
||
case RECORD_TYPE:
|
||
case UNION_TYPE:
|
||
case QUAL_UNION_TYPE:
|
||
/* When not optimizing, disregard register keyword for variables with
|
||
types containing methods, otherwise the methods won't be callable
|
||
from the debugger. */
|
||
if (TYPE_METHODS (TREE_TYPE (decl)))
|
||
return false;
|
||
break;
|
||
default:
|
||
break;
|
||
}
|
||
|
||
return true;
|
||
}
|
||
|
||
/* Return true if TYPE should be passed by invisible reference. */
|
||
|
||
bool
|
||
pass_by_reference (CUMULATIVE_ARGS *ca, enum machine_mode mode,
|
||
tree type, bool named_arg)
|
||
{
|
||
if (type)
|
||
{
|
||
/* If this type contains non-trivial constructors, then it is
|
||
forbidden for the middle-end to create any new copies. */
|
||
if (TREE_ADDRESSABLE (type))
|
||
return true;
|
||
|
||
/* GCC post 3.4 passes *all* variable sized types by reference. */
|
||
if (!TYPE_SIZE (type) || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
|
||
return true;
|
||
|
||
/* If a record type should be passed the same as its first (and only)
|
||
member, use the type and mode of that member. */
|
||
if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
|
||
{
|
||
type = TREE_TYPE (first_field (type));
|
||
mode = TYPE_MODE (type);
|
||
}
|
||
}
|
||
|
||
return targetm.calls.pass_by_reference (pack_cumulative_args (ca), mode,
|
||
type, named_arg);
|
||
}
|
||
|
||
/* Return true if TYPE, which is passed by reference, should be callee
|
||
copied instead of caller copied. */
|
||
|
||
bool
|
||
reference_callee_copied (CUMULATIVE_ARGS *ca, enum machine_mode mode,
|
||
tree type, bool named_arg)
|
||
{
|
||
if (type && TREE_ADDRESSABLE (type))
|
||
return false;
|
||
return targetm.calls.callee_copies (pack_cumulative_args (ca), mode, type,
|
||
named_arg);
|
||
}
|
||
|
||
/* Structures to communicate between the subroutines of assign_parms.
|
||
The first holds data persistent across all parameters, the second
|
||
is cleared out for each parameter. */
|
||
|
||
struct assign_parm_data_all
|
||
{
|
||
/* When INIT_CUMULATIVE_ARGS gets revamped, allocating CUMULATIVE_ARGS
|
||
should become a job of the target or otherwise encapsulated. */
|
||
CUMULATIVE_ARGS args_so_far_v;
|
||
cumulative_args_t args_so_far;
|
||
struct args_size stack_args_size;
|
||
tree function_result_decl;
|
||
tree orig_fnargs;
|
||
rtx first_conversion_insn;
|
||
rtx last_conversion_insn;
|
||
HOST_WIDE_INT pretend_args_size;
|
||
HOST_WIDE_INT extra_pretend_bytes;
|
||
int reg_parm_stack_space;
|
||
};
|
||
|
||
struct assign_parm_data_one
|
||
{
|
||
tree nominal_type;
|
||
tree passed_type;
|
||
rtx entry_parm;
|
||
rtx stack_parm;
|
||
enum machine_mode nominal_mode;
|
||
enum machine_mode passed_mode;
|
||
enum machine_mode promoted_mode;
|
||
struct locate_and_pad_arg_data locate;
|
||
int partial;
|
||
BOOL_BITFIELD named_arg : 1;
|
||
BOOL_BITFIELD passed_pointer : 1;
|
||
BOOL_BITFIELD on_stack : 1;
|
||
BOOL_BITFIELD loaded_in_reg : 1;
|
||
};
|
||
|
||
/* A subroutine of assign_parms. Initialize ALL. */
|
||
|
||
static void
|
||
assign_parms_initialize_all (struct assign_parm_data_all *all)
|
||
{
|
||
tree fntype ATTRIBUTE_UNUSED;
|
||
|
||
memset (all, 0, sizeof (*all));
|
||
|
||
fntype = TREE_TYPE (current_function_decl);
|
||
|
||
#ifdef INIT_CUMULATIVE_INCOMING_ARGS
|
||
INIT_CUMULATIVE_INCOMING_ARGS (all->args_so_far_v, fntype, NULL_RTX);
|
||
#else
|
||
INIT_CUMULATIVE_ARGS (all->args_so_far_v, fntype, NULL_RTX,
|
||
current_function_decl, -1);
|
||
#endif
|
||
all->args_so_far = pack_cumulative_args (&all->args_so_far_v);
|
||
|
||
#ifdef REG_PARM_STACK_SPACE
|
||
all->reg_parm_stack_space = REG_PARM_STACK_SPACE (current_function_decl);
|
||
#endif
|
||
}
|
||
|
||
/* If ARGS contains entries with complex types, split the entry into two
|
||
entries of the component type. Return a new list of substitutions are
|
||
needed, else the old list. */
|
||
|
||
static void
|
||
split_complex_args (VEC(tree, heap) **args)
|
||
{
|
||
unsigned i;
|
||
tree p;
|
||
|
||
FOR_EACH_VEC_ELT (tree, *args, i, p)
|
||
{
|
||
tree type = TREE_TYPE (p);
|
||
if (TREE_CODE (type) == COMPLEX_TYPE
|
||
&& targetm.calls.split_complex_arg (type))
|
||
{
|
||
tree decl;
|
||
tree subtype = TREE_TYPE (type);
|
||
bool addressable = TREE_ADDRESSABLE (p);
|
||
|
||
/* Rewrite the PARM_DECL's type with its component. */
|
||
p = copy_node (p);
|
||
TREE_TYPE (p) = subtype;
|
||
DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
|
||
DECL_MODE (p) = VOIDmode;
|
||
DECL_SIZE (p) = NULL;
|
||
DECL_SIZE_UNIT (p) = NULL;
|
||
/* If this arg must go in memory, put it in a pseudo here.
|
||
We can't allow it to go in memory as per normal parms,
|
||
because the usual place might not have the imag part
|
||
adjacent to the real part. */
|
||
DECL_ARTIFICIAL (p) = addressable;
|
||
DECL_IGNORED_P (p) = addressable;
|
||
TREE_ADDRESSABLE (p) = 0;
|
||
layout_decl (p, 0);
|
||
VEC_replace (tree, *args, i, p);
|
||
|
||
/* Build a second synthetic decl. */
|
||
decl = build_decl (EXPR_LOCATION (p),
|
||
PARM_DECL, NULL_TREE, subtype);
|
||
DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
|
||
DECL_ARTIFICIAL (decl) = addressable;
|
||
DECL_IGNORED_P (decl) = addressable;
|
||
layout_decl (decl, 0);
|
||
VEC_safe_insert (tree, heap, *args, ++i, decl);
|
||
}
|
||
}
|
||
}
|
||
|
||
/* A subroutine of assign_parms. Adjust the parameter list to incorporate
|
||
the hidden struct return argument, and (abi willing) complex args.
|
||
Return the new parameter list. */
|
||
|
||
static VEC(tree, heap) *
|
||
assign_parms_augmented_arg_list (struct assign_parm_data_all *all)
|
||
{
|
||
tree fndecl = current_function_decl;
|
||
tree fntype = TREE_TYPE (fndecl);
|
||
VEC(tree, heap) *fnargs = NULL;
|
||
tree arg;
|
||
|
||
for (arg = DECL_ARGUMENTS (fndecl); arg; arg = DECL_CHAIN (arg))
|
||
VEC_safe_push (tree, heap, fnargs, arg);
|
||
|
||
all->orig_fnargs = DECL_ARGUMENTS (fndecl);
|
||
|
||
/* If struct value address is treated as the first argument, make it so. */
|
||
if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
|
||
&& ! cfun->returns_pcc_struct
|
||
&& targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
|
||
{
|
||
tree type = build_pointer_type (TREE_TYPE (fntype));
|
||
tree decl;
|
||
|
||
decl = build_decl (DECL_SOURCE_LOCATION (fndecl),
|
||
PARM_DECL, get_identifier (".result_ptr"), type);
|
||
DECL_ARG_TYPE (decl) = type;
|
||
DECL_ARTIFICIAL (decl) = 1;
|
||
DECL_NAMELESS (decl) = 1;
|
||
TREE_CONSTANT (decl) = 1;
|
||
|
||
DECL_CHAIN (decl) = all->orig_fnargs;
|
||
all->orig_fnargs = decl;
|
||
VEC_safe_insert (tree, heap, fnargs, 0, decl);
|
||
|
||
all->function_result_decl = decl;
|
||
}
|
||
|
||
/* If the target wants to split complex arguments into scalars, do so. */
|
||
if (targetm.calls.split_complex_arg)
|
||
split_complex_args (&fnargs);
|
||
|
||
return fnargs;
|
||
}
|
||
|
||
/* A subroutine of assign_parms. Examine PARM and pull out type and mode
|
||
data for the parameter. Incorporate ABI specifics such as pass-by-
|
||
reference and type promotion. */
|
||
|
||
static void
|
||
assign_parm_find_data_types (struct assign_parm_data_all *all, tree parm,
|
||
struct assign_parm_data_one *data)
|
||
{
|
||
tree nominal_type, passed_type;
|
||
enum machine_mode nominal_mode, passed_mode, promoted_mode;
|
||
int unsignedp;
|
||
|
||
memset (data, 0, sizeof (*data));
|
||
|
||
/* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
|
||
if (!cfun->stdarg)
|
||
data->named_arg = 1; /* No variadic parms. */
|
||
else if (DECL_CHAIN (parm))
|
||
data->named_arg = 1; /* Not the last non-variadic parm. */
|
||
else if (targetm.calls.strict_argument_naming (all->args_so_far))
|
||
data->named_arg = 1; /* Only variadic ones are unnamed. */
|
||
else
|
||
data->named_arg = 0; /* Treat as variadic. */
|
||
|
||
nominal_type = TREE_TYPE (parm);
|
||
passed_type = DECL_ARG_TYPE (parm);
|
||
|
||
/* Look out for errors propagating this far. Also, if the parameter's
|
||
type is void then its value doesn't matter. */
|
||
if (TREE_TYPE (parm) == error_mark_node
|
||
/* This can happen after weird syntax errors
|
||
or if an enum type is defined among the parms. */
|
||
|| TREE_CODE (parm) != PARM_DECL
|
||
|| passed_type == NULL
|
||
|| VOID_TYPE_P (nominal_type))
|
||
{
|
||
nominal_type = passed_type = void_type_node;
|
||
nominal_mode = passed_mode = promoted_mode = VOIDmode;
|
||
goto egress;
|
||
}
|
||
|
||
/* Find mode of arg as it is passed, and mode of arg as it should be
|
||
during execution of this function. */
|
||
passed_mode = TYPE_MODE (passed_type);
|
||
nominal_mode = TYPE_MODE (nominal_type);
|
||
|
||
/* If the parm is to be passed as a transparent union or record, use the
|
||
type of the first field for the tests below. We have already verified
|
||
that the modes are the same. */
|
||
if ((TREE_CODE (passed_type) == UNION_TYPE
|
||
|| TREE_CODE (passed_type) == RECORD_TYPE)
|
||
&& TYPE_TRANSPARENT_AGGR (passed_type))
|
||
passed_type = TREE_TYPE (first_field (passed_type));
|
||
|
||
/* See if this arg was passed by invisible reference. */
|
||
if (pass_by_reference (&all->args_so_far_v, passed_mode,
|
||
passed_type, data->named_arg))
|
||
{
|
||
passed_type = nominal_type = build_pointer_type (passed_type);
|
||
data->passed_pointer = true;
|
||
passed_mode = nominal_mode = Pmode;
|
||
}
|
||
|
||
/* Find mode as it is passed by the ABI. */
|
||
unsignedp = TYPE_UNSIGNED (passed_type);
|
||
promoted_mode = promote_function_mode (passed_type, passed_mode, &unsignedp,
|
||
TREE_TYPE (current_function_decl), 0);
|
||
|
||
egress:
|
||
data->nominal_type = nominal_type;
|
||
data->passed_type = passed_type;
|
||
data->nominal_mode = nominal_mode;
|
||
data->passed_mode = passed_mode;
|
||
data->promoted_mode = promoted_mode;
|
||
}
|
||
|
||
/* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
|
||
|
||
static void
|
||
assign_parms_setup_varargs (struct assign_parm_data_all *all,
|
||
struct assign_parm_data_one *data, bool no_rtl)
|
||
{
|
||
int varargs_pretend_bytes = 0;
|
||
|
||
targetm.calls.setup_incoming_varargs (all->args_so_far,
|
||
data->promoted_mode,
|
||
data->passed_type,
|
||
&varargs_pretend_bytes, no_rtl);
|
||
|
||
/* If the back-end has requested extra stack space, record how much is
|
||
needed. Do not change pretend_args_size otherwise since it may be
|
||
nonzero from an earlier partial argument. */
|
||
if (varargs_pretend_bytes > 0)
|
||
all->pretend_args_size = varargs_pretend_bytes;
|
||
}
|
||
|
||
/* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
|
||
the incoming location of the current parameter. */
|
||
|
||
static void
|
||
assign_parm_find_entry_rtl (struct assign_parm_data_all *all,
|
||
struct assign_parm_data_one *data)
|
||
{
|
||
HOST_WIDE_INT pretend_bytes = 0;
|
||
rtx entry_parm;
|
||
bool in_regs;
|
||
|
||
if (data->promoted_mode == VOIDmode)
|
||
{
|
||
data->entry_parm = data->stack_parm = const0_rtx;
|
||
return;
|
||
}
|
||
|
||
entry_parm = targetm.calls.function_incoming_arg (all->args_so_far,
|
||
data->promoted_mode,
|
||
data->passed_type,
|
||
data->named_arg);
|
||
|
||
if (entry_parm == 0)
|
||
data->promoted_mode = data->passed_mode;
|
||
|
||
/* Determine parm's home in the stack, in case it arrives in the stack
|
||
or we should pretend it did. Compute the stack position and rtx where
|
||
the argument arrives and its size.
|
||
|
||
There is one complexity here: If this was a parameter that would
|
||
have been passed in registers, but wasn't only because it is
|
||
__builtin_va_alist, we want locate_and_pad_parm to treat it as if
|
||
it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
|
||
In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
|
||
as it was the previous time. */
|
||
in_regs = entry_parm != 0;
|
||
#ifdef STACK_PARMS_IN_REG_PARM_AREA
|
||
in_regs = true;
|
||
#endif
|
||
if (!in_regs && !data->named_arg)
|
||
{
|
||
if (targetm.calls.pretend_outgoing_varargs_named (all->args_so_far))
|
||
{
|
||
rtx tem;
|
||
tem = targetm.calls.function_incoming_arg (all->args_so_far,
|
||
data->promoted_mode,
|
||
data->passed_type, true);
|
||
in_regs = tem != NULL;
|
||
}
|
||
}
|
||
|
||
/* If this parameter was passed both in registers and in the stack, use
|
||
the copy on the stack. */
|
||
if (targetm.calls.must_pass_in_stack (data->promoted_mode,
|
||
data->passed_type))
|
||
entry_parm = 0;
|
||
|
||
if (entry_parm)
|
||
{
|
||
int partial;
|
||
|
||
partial = targetm.calls.arg_partial_bytes (all->args_so_far,
|
||
data->promoted_mode,
|
||
data->passed_type,
|
||
data->named_arg);
|
||
data->partial = partial;
|
||
|
||
/* The caller might already have allocated stack space for the
|
||
register parameters. */
|
||
if (partial != 0 && all->reg_parm_stack_space == 0)
|
||
{
|
||
/* Part of this argument is passed in registers and part
|
||
is passed on the stack. Ask the prologue code to extend
|
||
the stack part so that we can recreate the full value.
|
||
|
||
PRETEND_BYTES is the size of the registers we need to store.
|
||
CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
|
||
stack space that the prologue should allocate.
|
||
|
||
Internally, gcc assumes that the argument pointer is aligned
|
||
to STACK_BOUNDARY bits. This is used both for alignment
|
||
optimizations (see init_emit) and to locate arguments that are
|
||
aligned to more than PARM_BOUNDARY bits. We must preserve this
|
||
invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
|
||
a stack boundary. */
|
||
|
||
/* We assume at most one partial arg, and it must be the first
|
||
argument on the stack. */
|
||
gcc_assert (!all->extra_pretend_bytes && !all->pretend_args_size);
|
||
|
||
pretend_bytes = partial;
|
||
all->pretend_args_size = CEIL_ROUND (pretend_bytes, STACK_BYTES);
|
||
|
||
/* We want to align relative to the actual stack pointer, so
|
||
don't include this in the stack size until later. */
|
||
all->extra_pretend_bytes = all->pretend_args_size;
|
||
}
|
||
}
|
||
|
||
locate_and_pad_parm (data->promoted_mode, data->passed_type, in_regs,
|
||
entry_parm ? data->partial : 0, current_function_decl,
|
||
&all->stack_args_size, &data->locate);
|
||
|
||
/* Update parm_stack_boundary if this parameter is passed in the
|
||
stack. */
|
||
if (!in_regs && crtl->parm_stack_boundary < data->locate.boundary)
|
||
crtl->parm_stack_boundary = data->locate.boundary;
|
||
|
||
/* Adjust offsets to include the pretend args. */
|
||
pretend_bytes = all->extra_pretend_bytes - pretend_bytes;
|
||
data->locate.slot_offset.constant += pretend_bytes;
|
||
data->locate.offset.constant += pretend_bytes;
|
||
|
||
data->entry_parm = entry_parm;
|
||
}
|
||
|
||
/* A subroutine of assign_parms. If there is actually space on the stack
|
||
for this parm, count it in stack_args_size and return true. */
|
||
|
||
static bool
|
||
assign_parm_is_stack_parm (struct assign_parm_data_all *all,
|
||
struct assign_parm_data_one *data)
|
||
{
|
||
/* Trivially true if we've no incoming register. */
|
||
if (data->entry_parm == NULL)
|
||
;
|
||
/* Also true if we're partially in registers and partially not,
|
||
since we've arranged to drop the entire argument on the stack. */
|
||
else if (data->partial != 0)
|
||
;
|
||
/* Also true if the target says that it's passed in both registers
|
||
and on the stack. */
|
||
else if (GET_CODE (data->entry_parm) == PARALLEL
|
||
&& XEXP (XVECEXP (data->entry_parm, 0, 0), 0) == NULL_RTX)
|
||
;
|
||
/* Also true if the target says that there's stack allocated for
|
||
all register parameters. */
|
||
else if (all->reg_parm_stack_space > 0)
|
||
;
|
||
/* Otherwise, no, this parameter has no ABI defined stack slot. */
|
||
else
|
||
return false;
|
||
|
||
all->stack_args_size.constant += data->locate.size.constant;
|
||
if (data->locate.size.var)
|
||
ADD_PARM_SIZE (all->stack_args_size, data->locate.size.var);
|
||
|
||
return true;
|
||
}
|
||
|
||
/* A subroutine of assign_parms. Given that this parameter is allocated
|
||
stack space by the ABI, find it. */
|
||
|
||
static void
|
||
assign_parm_find_stack_rtl (tree parm, struct assign_parm_data_one *data)
|
||
{
|
||
rtx offset_rtx, stack_parm;
|
||
unsigned int align, boundary;
|
||
|
||
/* If we're passing this arg using a reg, make its stack home the
|
||
aligned stack slot. */
|
||
if (data->entry_parm)
|
||
offset_rtx = ARGS_SIZE_RTX (data->locate.slot_offset);
|
||
else
|
||
offset_rtx = ARGS_SIZE_RTX (data->locate.offset);
|
||
|
||
stack_parm = crtl->args.internal_arg_pointer;
|
||
if (offset_rtx != const0_rtx)
|
||
stack_parm = gen_rtx_PLUS (Pmode, stack_parm, offset_rtx);
|
||
stack_parm = gen_rtx_MEM (data->promoted_mode, stack_parm);
|
||
|
||
if (!data->passed_pointer)
|
||
{
|
||
set_mem_attributes (stack_parm, parm, 1);
|
||
/* set_mem_attributes could set MEM_SIZE to the passed mode's size,
|
||
while promoted mode's size is needed. */
|
||
if (data->promoted_mode != BLKmode
|
||
&& data->promoted_mode != DECL_MODE (parm))
|
||
{
|
||
set_mem_size (stack_parm, GET_MODE_SIZE (data->promoted_mode));
|
||
if (MEM_EXPR (stack_parm) && MEM_OFFSET_KNOWN_P (stack_parm))
|
||
{
|
||
int offset = subreg_lowpart_offset (DECL_MODE (parm),
|
||
data->promoted_mode);
|
||
if (offset)
|
||
set_mem_offset (stack_parm, MEM_OFFSET (stack_parm) - offset);
|
||
}
|
||
}
|
||
}
|
||
|
||
boundary = data->locate.boundary;
|
||
align = BITS_PER_UNIT;
|
||
|
||
/* If we're padding upward, we know that the alignment of the slot
|
||
is TARGET_FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
|
||
intentionally forcing upward padding. Otherwise we have to come
|
||
up with a guess at the alignment based on OFFSET_RTX. */
|
||
if (data->locate.where_pad != downward || data->entry_parm)
|
||
align = boundary;
|
||
else if (CONST_INT_P (offset_rtx))
|
||
{
|
||
align = INTVAL (offset_rtx) * BITS_PER_UNIT | boundary;
|
||
align = align & -align;
|
||
}
|
||
set_mem_align (stack_parm, align);
|
||
|
||
if (data->entry_parm)
|
||
set_reg_attrs_for_parm (data->entry_parm, stack_parm);
|
||
|
||
data->stack_parm = stack_parm;
|
||
}
|
||
|
||
/* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
|
||
always valid and contiguous. */
|
||
|
||
static void
|
||
assign_parm_adjust_entry_rtl (struct assign_parm_data_one *data)
|
||
{
|
||
rtx entry_parm = data->entry_parm;
|
||
rtx stack_parm = data->stack_parm;
|
||
|
||
/* If this parm was passed part in regs and part in memory, pretend it
|
||
arrived entirely in memory by pushing the register-part onto the stack.
|
||
In the special case of a DImode or DFmode that is split, we could put
|
||
it together in a pseudoreg directly, but for now that's not worth
|
||
bothering with. */
|
||
if (data->partial != 0)
|
||
{
|
||
/* Handle calls that pass values in multiple non-contiguous
|
||
locations. The Irix 6 ABI has examples of this. */
|
||
if (GET_CODE (entry_parm) == PARALLEL)
|
||
emit_group_store (validize_mem (stack_parm), entry_parm,
|
||
data->passed_type,
|
||
int_size_in_bytes (data->passed_type));
|
||
else
|
||
{
|
||
gcc_assert (data->partial % UNITS_PER_WORD == 0);
|
||
move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm),
|
||
data->partial / UNITS_PER_WORD);
|
||
}
|
||
|
||
entry_parm = stack_parm;
|
||
}
|
||
|
||
/* If we didn't decide this parm came in a register, by default it came
|
||
on the stack. */
|
||
else if (entry_parm == NULL)
|
||
entry_parm = stack_parm;
|
||
|
||
/* When an argument is passed in multiple locations, we can't make use
|
||
of this information, but we can save some copying if the whole argument
|
||
is passed in a single register. */
|
||
else if (GET_CODE (entry_parm) == PARALLEL
|
||
&& data->nominal_mode != BLKmode
|
||
&& data->passed_mode != BLKmode)
|
||
{
|
||
size_t i, len = XVECLEN (entry_parm, 0);
|
||
|
||
for (i = 0; i < len; i++)
|
||
if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
|
||
&& REG_P (XEXP (XVECEXP (entry_parm, 0, i), 0))
|
||
&& (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
|
||
== data->passed_mode)
|
||
&& INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
|
||
{
|
||
entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
|
||
break;
|
||
}
|
||
}
|
||
|
||
data->entry_parm = entry_parm;
|
||
}
|
||
|
||
/* A subroutine of assign_parms. Reconstitute any values which were
|
||
passed in multiple registers and would fit in a single register. */
|
||
|
||
static void
|
||
assign_parm_remove_parallels (struct assign_parm_data_one *data)
|
||
{
|
||
rtx entry_parm = data->entry_parm;
|
||
|
||
/* Convert the PARALLEL to a REG of the same mode as the parallel.
|
||
This can be done with register operations rather than on the
|
||
stack, even if we will store the reconstituted parameter on the
|
||
stack later. */
|
||
if (GET_CODE (entry_parm) == PARALLEL && GET_MODE (entry_parm) != BLKmode)
|
||
{
|
||
rtx parmreg = gen_reg_rtx (GET_MODE (entry_parm));
|
||
emit_group_store (parmreg, entry_parm, data->passed_type,
|
||
GET_MODE_SIZE (GET_MODE (entry_parm)));
|
||
entry_parm = parmreg;
|
||
}
|
||
|
||
data->entry_parm = entry_parm;
|
||
}
|
||
|
||
/* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
|
||
always valid and properly aligned. */
|
||
|
||
static void
|
||
assign_parm_adjust_stack_rtl (struct assign_parm_data_one *data)
|
||
{
|
||
rtx stack_parm = data->stack_parm;
|
||
|
||
/* If we can't trust the parm stack slot to be aligned enough for its
|
||
ultimate type, don't use that slot after entry. We'll make another
|
||
stack slot, if we need one. */
|
||
if (stack_parm
|
||
&& ((STRICT_ALIGNMENT
|
||
&& GET_MODE_ALIGNMENT (data->nominal_mode) > MEM_ALIGN (stack_parm))
|
||
|| (data->nominal_type
|
||
&& TYPE_ALIGN (data->nominal_type) > MEM_ALIGN (stack_parm)
|
||
&& MEM_ALIGN (stack_parm) < PREFERRED_STACK_BOUNDARY)))
|
||
stack_parm = NULL;
|
||
|
||
/* If parm was passed in memory, and we need to convert it on entry,
|
||
don't store it back in that same slot. */
|
||
else if (data->entry_parm == stack_parm
|
||
&& data->nominal_mode != BLKmode
|
||
&& data->nominal_mode != data->passed_mode)
|
||
stack_parm = NULL;
|
||
|
||
/* If stack protection is in effect for this function, don't leave any
|
||
pointers in their passed stack slots. */
|
||
else if (crtl->stack_protect_guard
|
||
&& (flag_stack_protect == 2
|
||
|| data->passed_pointer
|
||
|| POINTER_TYPE_P (data->nominal_type)))
|
||
stack_parm = NULL;
|
||
|
||
data->stack_parm = stack_parm;
|
||
}
|
||
|
||
/* A subroutine of assign_parms. Return true if the current parameter
|
||
should be stored as a BLKmode in the current frame. */
|
||
|
||
static bool
|
||
assign_parm_setup_block_p (struct assign_parm_data_one *data)
|
||
{
|
||
if (data->nominal_mode == BLKmode)
|
||
return true;
|
||
if (GET_MODE (data->entry_parm) == BLKmode)
|
||
return true;
|
||
|
||
#ifdef BLOCK_REG_PADDING
|
||
/* Only assign_parm_setup_block knows how to deal with register arguments
|
||
that are padded at the least significant end. */
|
||
if (REG_P (data->entry_parm)
|
||
&& GET_MODE_SIZE (data->promoted_mode) < UNITS_PER_WORD
|
||
&& (BLOCK_REG_PADDING (data->passed_mode, data->passed_type, 1)
|
||
== (BYTES_BIG_ENDIAN ? upward : downward)))
|
||
return true;
|
||
#endif
|
||
|
||
return false;
|
||
}
|
||
|
||
/* A subroutine of assign_parms. Arrange for the parameter to be
|
||
present and valid in DATA->STACK_RTL. */
|
||
|
||
static void
|
||
assign_parm_setup_block (struct assign_parm_data_all *all,
|
||
tree parm, struct assign_parm_data_one *data)
|
||
{
|
||
rtx entry_parm = data->entry_parm;
|
||
rtx stack_parm = data->stack_parm;
|
||
HOST_WIDE_INT size;
|
||
HOST_WIDE_INT size_stored;
|
||
|
||
if (GET_CODE (entry_parm) == PARALLEL)
|
||
entry_parm = emit_group_move_into_temps (entry_parm);
|
||
|
||
size = int_size_in_bytes (data->passed_type);
|
||
size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
|
||
if (stack_parm == 0)
|
||
{
|
||
DECL_ALIGN (parm) = MAX (DECL_ALIGN (parm), BITS_PER_WORD);
|
||
stack_parm = assign_stack_local (BLKmode, size_stored,
|
||
DECL_ALIGN (parm));
|
||
if (GET_MODE_SIZE (GET_MODE (entry_parm)) == size)
|
||
PUT_MODE (stack_parm, GET_MODE (entry_parm));
|
||
set_mem_attributes (stack_parm, parm, 1);
|
||
}
|
||
|
||
/* If a BLKmode arrives in registers, copy it to a stack slot. Handle
|
||
calls that pass values in multiple non-contiguous locations. */
|
||
if (REG_P (entry_parm) || GET_CODE (entry_parm) == PARALLEL)
|
||
{
|
||
rtx mem;
|
||
|
||
/* Note that we will be storing an integral number of words.
|
||
So we have to be careful to ensure that we allocate an
|
||
integral number of words. We do this above when we call
|
||
assign_stack_local if space was not allocated in the argument
|
||
list. If it was, this will not work if PARM_BOUNDARY is not
|
||
a multiple of BITS_PER_WORD. It isn't clear how to fix this
|
||
if it becomes a problem. Exception is when BLKmode arrives
|
||
with arguments not conforming to word_mode. */
|
||
|
||
if (data->stack_parm == 0)
|
||
;
|
||
else if (GET_CODE (entry_parm) == PARALLEL)
|
||
;
|
||
else
|
||
gcc_assert (!size || !(PARM_BOUNDARY % BITS_PER_WORD));
|
||
|
||
mem = validize_mem (stack_parm);
|
||
|
||
/* Handle values in multiple non-contiguous locations. */
|
||
if (GET_CODE (entry_parm) == PARALLEL)
|
||
{
|
||
push_to_sequence2 (all->first_conversion_insn,
|
||
all->last_conversion_insn);
|
||
emit_group_store (mem, entry_parm, data->passed_type, size);
|
||
all->first_conversion_insn = get_insns ();
|
||
all->last_conversion_insn = get_last_insn ();
|
||
end_sequence ();
|
||
}
|
||
|
||
else if (size == 0)
|
||
;
|
||
|
||
/* If SIZE is that of a mode no bigger than a word, just use
|
||
that mode's store operation. */
|
||
else if (size <= UNITS_PER_WORD)
|
||
{
|
||
enum machine_mode mode
|
||
= mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
|
||
|
||
if (mode != BLKmode
|
||
#ifdef BLOCK_REG_PADDING
|
||
&& (size == UNITS_PER_WORD
|
||
|| (BLOCK_REG_PADDING (mode, data->passed_type, 1)
|
||
!= (BYTES_BIG_ENDIAN ? upward : downward)))
|
||
#endif
|
||
)
|
||
{
|
||
rtx reg;
|
||
|
||
/* We are really truncating a word_mode value containing
|
||
SIZE bytes into a value of mode MODE. If such an
|
||
operation requires no actual instructions, we can refer
|
||
to the value directly in mode MODE, otherwise we must
|
||
start with the register in word_mode and explicitly
|
||
convert it. */
|
||
if (TRULY_NOOP_TRUNCATION (size * BITS_PER_UNIT, BITS_PER_WORD))
|
||
reg = gen_rtx_REG (mode, REGNO (entry_parm));
|
||
else
|
||
{
|
||
reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
|
||
reg = convert_to_mode (mode, copy_to_reg (reg), 1);
|
||
}
|
||
emit_move_insn (change_address (mem, mode, 0), reg);
|
||
}
|
||
|
||
/* Blocks smaller than a word on a BYTES_BIG_ENDIAN
|
||
machine must be aligned to the left before storing
|
||
to memory. Note that the previous test doesn't
|
||
handle all cases (e.g. SIZE == 3). */
|
||
else if (size != UNITS_PER_WORD
|
||
#ifdef BLOCK_REG_PADDING
|
||
&& (BLOCK_REG_PADDING (mode, data->passed_type, 1)
|
||
== downward)
|
||
#else
|
||
&& BYTES_BIG_ENDIAN
|
||
#endif
|
||
)
|
||
{
|
||
rtx tem, x;
|
||
int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
|
||
rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
|
||
|
||
x = expand_shift (LSHIFT_EXPR, word_mode, reg, by, NULL_RTX, 1);
|
||
tem = change_address (mem, word_mode, 0);
|
||
emit_move_insn (tem, x);
|
||
}
|
||
else
|
||
move_block_from_reg (REGNO (entry_parm), mem,
|
||
size_stored / UNITS_PER_WORD);
|
||
}
|
||
else
|
||
move_block_from_reg (REGNO (entry_parm), mem,
|
||
size_stored / UNITS_PER_WORD);
|
||
}
|
||
else if (data->stack_parm == 0)
|
||
{
|
||
push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
|
||
emit_block_move (stack_parm, data->entry_parm, GEN_INT (size),
|
||
BLOCK_OP_NORMAL);
|
||
all->first_conversion_insn = get_insns ();
|
||
all->last_conversion_insn = get_last_insn ();
|
||
end_sequence ();
|
||
}
|
||
|
||
data->stack_parm = stack_parm;
|
||
SET_DECL_RTL (parm, stack_parm);
|
||
}
|
||
|
||
/* A subroutine of assign_parms. Allocate a pseudo to hold the current
|
||
parameter. Get it there. Perform all ABI specified conversions. */
|
||
|
||
static void
|
||
assign_parm_setup_reg (struct assign_parm_data_all *all, tree parm,
|
||
struct assign_parm_data_one *data)
|
||
{
|
||
rtx parmreg, validated_mem;
|
||
rtx equiv_stack_parm;
|
||
enum machine_mode promoted_nominal_mode;
|
||
int unsignedp = TYPE_UNSIGNED (TREE_TYPE (parm));
|
||
bool did_conversion = false;
|
||
bool need_conversion, moved;
|
||
|
||
/* Store the parm in a pseudoregister during the function, but we may
|
||
need to do it in a wider mode. Using 2 here makes the result
|
||
consistent with promote_decl_mode and thus expand_expr_real_1. */
|
||
promoted_nominal_mode
|
||
= promote_function_mode (data->nominal_type, data->nominal_mode, &unsignedp,
|
||
TREE_TYPE (current_function_decl), 2);
|
||
|
||
parmreg = gen_reg_rtx (promoted_nominal_mode);
|
||
|
||
if (!DECL_ARTIFICIAL (parm))
|
||
mark_user_reg (parmreg);
|
||
|
||
/* If this was an item that we received a pointer to,
|
||
set DECL_RTL appropriately. */
|
||
if (data->passed_pointer)
|
||
{
|
||
rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data->passed_type)), parmreg);
|
||
set_mem_attributes (x, parm, 1);
|
||
SET_DECL_RTL (parm, x);
|
||
}
|
||
else
|
||
SET_DECL_RTL (parm, parmreg);
|
||
|
||
assign_parm_remove_parallels (data);
|
||
|
||
/* Copy the value into the register, thus bridging between
|
||
assign_parm_find_data_types and expand_expr_real_1. */
|
||
|
||
equiv_stack_parm = data->stack_parm;
|
||
validated_mem = validize_mem (data->entry_parm);
|
||
|
||
need_conversion = (data->nominal_mode != data->passed_mode
|
||
|| promoted_nominal_mode != data->promoted_mode);
|
||
moved = false;
|
||
|
||
if (need_conversion
|
||
&& GET_MODE_CLASS (data->nominal_mode) == MODE_INT
|
||
&& data->nominal_mode == data->passed_mode
|
||
&& data->nominal_mode == GET_MODE (data->entry_parm))
|
||
{
|
||
/* ENTRY_PARM has been converted to PROMOTED_MODE, its
|
||
mode, by the caller. We now have to convert it to
|
||
NOMINAL_MODE, if different. However, PARMREG may be in
|
||
a different mode than NOMINAL_MODE if it is being stored
|
||
promoted.
|
||
|
||
If ENTRY_PARM is a hard register, it might be in a register
|
||
not valid for operating in its mode (e.g., an odd-numbered
|
||
register for a DFmode). In that case, moves are the only
|
||
thing valid, so we can't do a convert from there. This
|
||
occurs when the calling sequence allow such misaligned
|
||
usages.
|
||
|
||
In addition, the conversion may involve a call, which could
|
||
clobber parameters which haven't been copied to pseudo
|
||
registers yet.
|
||
|
||
First, we try to emit an insn which performs the necessary
|
||
conversion. We verify that this insn does not clobber any
|
||
hard registers. */
|
||
|
||
enum insn_code icode;
|
||
rtx op0, op1;
|
||
|
||
icode = can_extend_p (promoted_nominal_mode, data->passed_mode,
|
||
unsignedp);
|
||
|
||
op0 = parmreg;
|
||
op1 = validated_mem;
|
||
if (icode != CODE_FOR_nothing
|
||
&& insn_operand_matches (icode, 0, op0)
|
||
&& insn_operand_matches (icode, 1, op1))
|
||
{
|
||
enum rtx_code code = unsignedp ? ZERO_EXTEND : SIGN_EXTEND;
|
||
rtx insn, insns, t = op1;
|
||
HARD_REG_SET hardregs;
|
||
|
||
start_sequence ();
|
||
/* If op1 is a hard register that is likely spilled, first
|
||
force it into a pseudo, otherwise combiner might extend
|
||
its lifetime too much. */
|
||
if (GET_CODE (t) == SUBREG)
|
||
t = SUBREG_REG (t);
|
||
if (REG_P (t)
|
||
&& HARD_REGISTER_P (t)
|
||
&& ! TEST_HARD_REG_BIT (fixed_reg_set, REGNO (t))
|
||
&& targetm.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (t))))
|
||
{
|
||
t = gen_reg_rtx (GET_MODE (op1));
|
||
emit_move_insn (t, op1);
|
||
}
|
||
else
|
||
t = op1;
|
||
insn = gen_extend_insn (op0, t, promoted_nominal_mode,
|
||
data->passed_mode, unsignedp);
|
||
emit_insn (insn);
|
||
insns = get_insns ();
|
||
|
||
moved = true;
|
||
CLEAR_HARD_REG_SET (hardregs);
|
||
for (insn = insns; insn && moved; insn = NEXT_INSN (insn))
|
||
{
|
||
if (INSN_P (insn))
|
||
note_stores (PATTERN (insn), record_hard_reg_sets,
|
||
&hardregs);
|
||
if (!hard_reg_set_empty_p (hardregs))
|
||
moved = false;
|
||
}
|
||
|
||
end_sequence ();
|
||
|
||
if (moved)
|
||
{
|
||
emit_insn (insns);
|
||
if (equiv_stack_parm != NULL_RTX)
|
||
equiv_stack_parm = gen_rtx_fmt_e (code, GET_MODE (parmreg),
|
||
equiv_stack_parm);
|
||
}
|
||
}
|
||
}
|
||
|
||
if (moved)
|
||
/* Nothing to do. */
|
||
;
|
||
else if (need_conversion)
|
||
{
|
||
/* We did not have an insn to convert directly, or the sequence
|
||
generated appeared unsafe. We must first copy the parm to a
|
||
pseudo reg, and save the conversion until after all
|
||
parameters have been moved. */
|
||
|
||
int save_tree_used;
|
||
rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
|
||
|
||
emit_move_insn (tempreg, validated_mem);
|
||
|
||
push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
|
||
tempreg = convert_to_mode (data->nominal_mode, tempreg, unsignedp);
|
||
|
||
if (GET_CODE (tempreg) == SUBREG
|
||
&& GET_MODE (tempreg) == data->nominal_mode
|
||
&& REG_P (SUBREG_REG (tempreg))
|
||
&& data->nominal_mode == data->passed_mode
|
||
&& GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (data->entry_parm)
|
||
&& GET_MODE_SIZE (GET_MODE (tempreg))
|
||
< GET_MODE_SIZE (GET_MODE (data->entry_parm)))
|
||
{
|
||
/* The argument is already sign/zero extended, so note it
|
||
into the subreg. */
|
||
SUBREG_PROMOTED_VAR_P (tempreg) = 1;
|
||
SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
|
||
}
|
||
|
||
/* TREE_USED gets set erroneously during expand_assignment. */
|
||
save_tree_used = TREE_USED (parm);
|
||
expand_assignment (parm, make_tree (data->nominal_type, tempreg), false);
|
||
TREE_USED (parm) = save_tree_used;
|
||
all->first_conversion_insn = get_insns ();
|
||
all->last_conversion_insn = get_last_insn ();
|
||
end_sequence ();
|
||
|
||
did_conversion = true;
|
||
}
|
||
else
|
||
emit_move_insn (parmreg, validated_mem);
|
||
|
||
/* If we were passed a pointer but the actual value can safely live
|
||
in a register, put it in one. */
|
||
if (data->passed_pointer
|
||
&& TYPE_MODE (TREE_TYPE (parm)) != BLKmode
|
||
/* If by-reference argument was promoted, demote it. */
|
||
&& (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
|
||
|| use_register_for_decl (parm)))
|
||
{
|
||
/* We can't use nominal_mode, because it will have been set to
|
||
Pmode above. We must use the actual mode of the parm. */
|
||
parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
|
||
mark_user_reg (parmreg);
|
||
|
||
if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
|
||
{
|
||
rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
|
||
int unsigned_p = TYPE_UNSIGNED (TREE_TYPE (parm));
|
||
|
||
push_to_sequence2 (all->first_conversion_insn,
|
||
all->last_conversion_insn);
|
||
emit_move_insn (tempreg, DECL_RTL (parm));
|
||
tempreg = convert_to_mode (GET_MODE (parmreg), tempreg, unsigned_p);
|
||
emit_move_insn (parmreg, tempreg);
|
||
all->first_conversion_insn = get_insns ();
|
||
all->last_conversion_insn = get_last_insn ();
|
||
end_sequence ();
|
||
|
||
did_conversion = true;
|
||
}
|
||
else
|
||
emit_move_insn (parmreg, DECL_RTL (parm));
|
||
|
||
SET_DECL_RTL (parm, parmreg);
|
||
|
||
/* STACK_PARM is the pointer, not the parm, and PARMREG is
|
||
now the parm. */
|
||
data->stack_parm = NULL;
|
||
}
|
||
|
||
/* Mark the register as eliminable if we did no conversion and it was
|
||
copied from memory at a fixed offset, and the arg pointer was not
|
||
copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
|
||
offset formed an invalid address, such memory-equivalences as we
|
||
make here would screw up life analysis for it. */
|
||
if (data->nominal_mode == data->passed_mode
|
||
&& !did_conversion
|
||
&& data->stack_parm != 0
|
||
&& MEM_P (data->stack_parm)
|
||
&& data->locate.offset.var == 0
|
||
&& reg_mentioned_p (virtual_incoming_args_rtx,
|
||
XEXP (data->stack_parm, 0)))
|
||
{
|
||
rtx linsn = get_last_insn ();
|
||
rtx sinsn, set;
|
||
|
||
/* Mark complex types separately. */
|
||
if (GET_CODE (parmreg) == CONCAT)
|
||
{
|
||
enum machine_mode submode
|
||
= GET_MODE_INNER (GET_MODE (parmreg));
|
||
int regnor = REGNO (XEXP (parmreg, 0));
|
||
int regnoi = REGNO (XEXP (parmreg, 1));
|
||
rtx stackr = adjust_address_nv (data->stack_parm, submode, 0);
|
||
rtx stacki = adjust_address_nv (data->stack_parm, submode,
|
||
GET_MODE_SIZE (submode));
|
||
|
||
/* Scan backwards for the set of the real and
|
||
imaginary parts. */
|
||
for (sinsn = linsn; sinsn != 0;
|
||
sinsn = prev_nonnote_insn (sinsn))
|
||
{
|
||
set = single_set (sinsn);
|
||
if (set == 0)
|
||
continue;
|
||
|
||
if (SET_DEST (set) == regno_reg_rtx [regnoi])
|
||
set_unique_reg_note (sinsn, REG_EQUIV, stacki);
|
||
else if (SET_DEST (set) == regno_reg_rtx [regnor])
|
||
set_unique_reg_note (sinsn, REG_EQUIV, stackr);
|
||
}
|
||
}
|
||
else
|
||
set_dst_reg_note (linsn, REG_EQUIV, equiv_stack_parm, parmreg);
|
||
}
|
||
|
||
/* For pointer data type, suggest pointer register. */
|
||
if (POINTER_TYPE_P (TREE_TYPE (parm)))
|
||
mark_reg_pointer (parmreg,
|
||
TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
|
||
}
|
||
|
||
/* A subroutine of assign_parms. Allocate stack space to hold the current
|
||
parameter. Get it there. Perform all ABI specified conversions. */
|
||
|
||
static void
|
||
assign_parm_setup_stack (struct assign_parm_data_all *all, tree parm,
|
||
struct assign_parm_data_one *data)
|
||
{
|
||
/* Value must be stored in the stack slot STACK_PARM during function
|
||
execution. */
|
||
bool to_conversion = false;
|
||
|
||
assign_parm_remove_parallels (data);
|
||
|
||
if (data->promoted_mode != data->nominal_mode)
|
||
{
|
||
/* Conversion is required. */
|
||
rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
|
||
|
||
emit_move_insn (tempreg, validize_mem (data->entry_parm));
|
||
|
||
push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
|
||
to_conversion = true;
|
||
|
||
data->entry_parm = convert_to_mode (data->nominal_mode, tempreg,
|
||
TYPE_UNSIGNED (TREE_TYPE (parm)));
|
||
|
||
if (data->stack_parm)
|
||
{
|
||
int offset = subreg_lowpart_offset (data->nominal_mode,
|
||
GET_MODE (data->stack_parm));
|
||
/* ??? This may need a big-endian conversion on sparc64. */
|
||
data->stack_parm
|
||
= adjust_address (data->stack_parm, data->nominal_mode, 0);
|
||
if (offset && MEM_OFFSET_KNOWN_P (data->stack_parm))
|
||
set_mem_offset (data->stack_parm,
|
||
MEM_OFFSET (data->stack_parm) + offset);
|
||
}
|
||
}
|
||
|
||
if (data->entry_parm != data->stack_parm)
|
||
{
|
||
rtx src, dest;
|
||
|
||
if (data->stack_parm == 0)
|
||
{
|
||
int align = STACK_SLOT_ALIGNMENT (data->passed_type,
|
||
GET_MODE (data->entry_parm),
|
||
TYPE_ALIGN (data->passed_type));
|
||
data->stack_parm
|
||
= assign_stack_local (GET_MODE (data->entry_parm),
|
||
GET_MODE_SIZE (GET_MODE (data->entry_parm)),
|
||
align);
|
||
set_mem_attributes (data->stack_parm, parm, 1);
|
||
}
|
||
|
||
dest = validize_mem (data->stack_parm);
|
||
src = validize_mem (data->entry_parm);
|
||
|
||
if (MEM_P (src))
|
||
{
|
||
/* Use a block move to handle potentially misaligned entry_parm. */
|
||
if (!to_conversion)
|
||
push_to_sequence2 (all->first_conversion_insn,
|
||
all->last_conversion_insn);
|
||
to_conversion = true;
|
||
|
||
emit_block_move (dest, src,
|
||
GEN_INT (int_size_in_bytes (data->passed_type)),
|
||
BLOCK_OP_NORMAL);
|
||
}
|
||
else
|
||
emit_move_insn (dest, src);
|
||
}
|
||
|
||
if (to_conversion)
|
||
{
|
||
all->first_conversion_insn = get_insns ();
|
||
all->last_conversion_insn = get_last_insn ();
|
||
end_sequence ();
|
||
}
|
||
|
||
SET_DECL_RTL (parm, data->stack_parm);
|
||
}
|
||
|
||
/* A subroutine of assign_parms. If the ABI splits complex arguments, then
|
||
undo the frobbing that we did in assign_parms_augmented_arg_list. */
|
||
|
||
static void
|
||
assign_parms_unsplit_complex (struct assign_parm_data_all *all,
|
||
VEC(tree, heap) *fnargs)
|
||
{
|
||
tree parm;
|
||
tree orig_fnargs = all->orig_fnargs;
|
||
unsigned i = 0;
|
||
|
||
for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm), ++i)
|
||
{
|
||
if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
|
||
&& targetm.calls.split_complex_arg (TREE_TYPE (parm)))
|
||
{
|
||
rtx tmp, real, imag;
|
||
enum machine_mode inner = GET_MODE_INNER (DECL_MODE (parm));
|
||
|
||
real = DECL_RTL (VEC_index (tree, fnargs, i));
|
||
imag = DECL_RTL (VEC_index (tree, fnargs, i + 1));
|
||
if (inner != GET_MODE (real))
|
||
{
|
||
real = gen_lowpart_SUBREG (inner, real);
|
||
imag = gen_lowpart_SUBREG (inner, imag);
|
||
}
|
||
|
||
if (TREE_ADDRESSABLE (parm))
|
||
{
|
||
rtx rmem, imem;
|
||
HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (parm));
|
||
int align = STACK_SLOT_ALIGNMENT (TREE_TYPE (parm),
|
||
DECL_MODE (parm),
|
||
TYPE_ALIGN (TREE_TYPE (parm)));
|
||
|
||
/* split_complex_arg put the real and imag parts in
|
||
pseudos. Move them to memory. */
|
||
tmp = assign_stack_local (DECL_MODE (parm), size, align);
|
||
set_mem_attributes (tmp, parm, 1);
|
||
rmem = adjust_address_nv (tmp, inner, 0);
|
||
imem = adjust_address_nv (tmp, inner, GET_MODE_SIZE (inner));
|
||
push_to_sequence2 (all->first_conversion_insn,
|
||
all->last_conversion_insn);
|
||
emit_move_insn (rmem, real);
|
||
emit_move_insn (imem, imag);
|
||
all->first_conversion_insn = get_insns ();
|
||
all->last_conversion_insn = get_last_insn ();
|
||
end_sequence ();
|
||
}
|
||
else
|
||
tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
|
||
SET_DECL_RTL (parm, tmp);
|
||
|
||
real = DECL_INCOMING_RTL (VEC_index (tree, fnargs, i));
|
||
imag = DECL_INCOMING_RTL (VEC_index (tree, fnargs, i + 1));
|
||
if (inner != GET_MODE (real))
|
||
{
|
||
real = gen_lowpart_SUBREG (inner, real);
|
||
imag = gen_lowpart_SUBREG (inner, imag);
|
||
}
|
||
tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
|
||
set_decl_incoming_rtl (parm, tmp, false);
|
||
i++;
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Assign RTL expressions to the function's parameters. This may involve
|
||
copying them into registers and using those registers as the DECL_RTL. */
|
||
|
||
static void
|
||
assign_parms (tree fndecl)
|
||
{
|
||
struct assign_parm_data_all all;
|
||
tree parm;
|
||
VEC(tree, heap) *fnargs;
|
||
unsigned i;
|
||
|
||
crtl->args.internal_arg_pointer
|
||
= targetm.calls.internal_arg_pointer ();
|
||
|
||
assign_parms_initialize_all (&all);
|
||
fnargs = assign_parms_augmented_arg_list (&all);
|
||
|
||
FOR_EACH_VEC_ELT (tree, fnargs, i, parm)
|
||
{
|
||
struct assign_parm_data_one data;
|
||
|
||
/* Extract the type of PARM; adjust it according to ABI. */
|
||
assign_parm_find_data_types (&all, parm, &data);
|
||
|
||
/* Early out for errors and void parameters. */
|
||
if (data.passed_mode == VOIDmode)
|
||
{
|
||
SET_DECL_RTL (parm, const0_rtx);
|
||
DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
|
||
continue;
|
||
}
|
||
|
||
/* Estimate stack alignment from parameter alignment. */
|
||
if (SUPPORTS_STACK_ALIGNMENT)
|
||
{
|
||
unsigned int align
|
||
= targetm.calls.function_arg_boundary (data.promoted_mode,
|
||
data.passed_type);
|
||
align = MINIMUM_ALIGNMENT (data.passed_type, data.promoted_mode,
|
||
align);
|
||
if (TYPE_ALIGN (data.nominal_type) > align)
|
||
align = MINIMUM_ALIGNMENT (data.nominal_type,
|
||
TYPE_MODE (data.nominal_type),
|
||
TYPE_ALIGN (data.nominal_type));
|
||
if (crtl->stack_alignment_estimated < align)
|
||
{
|
||
gcc_assert (!crtl->stack_realign_processed);
|
||
crtl->stack_alignment_estimated = align;
|
||
}
|
||
}
|
||
|
||
if (cfun->stdarg && !DECL_CHAIN (parm))
|
||
assign_parms_setup_varargs (&all, &data, false);
|
||
|
||
/* Find out where the parameter arrives in this function. */
|
||
assign_parm_find_entry_rtl (&all, &data);
|
||
|
||
/* Find out where stack space for this parameter might be. */
|
||
if (assign_parm_is_stack_parm (&all, &data))
|
||
{
|
||
assign_parm_find_stack_rtl (parm, &data);
|
||
assign_parm_adjust_entry_rtl (&data);
|
||
}
|
||
|
||
/* Record permanently how this parm was passed. */
|
||
if (data.passed_pointer)
|
||
{
|
||
rtx incoming_rtl
|
||
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data.passed_type)),
|
||
data.entry_parm);
|
||
set_decl_incoming_rtl (parm, incoming_rtl, true);
|
||
}
|
||
else
|
||
set_decl_incoming_rtl (parm, data.entry_parm, false);
|
||
|
||
/* Update info on where next arg arrives in registers. */
|
||
targetm.calls.function_arg_advance (all.args_so_far, data.promoted_mode,
|
||
data.passed_type, data.named_arg);
|
||
|
||
assign_parm_adjust_stack_rtl (&data);
|
||
|
||
if (assign_parm_setup_block_p (&data))
|
||
assign_parm_setup_block (&all, parm, &data);
|
||
else if (data.passed_pointer || use_register_for_decl (parm))
|
||
assign_parm_setup_reg (&all, parm, &data);
|
||
else
|
||
assign_parm_setup_stack (&all, parm, &data);
|
||
}
|
||
|
||
if (targetm.calls.split_complex_arg)
|
||
assign_parms_unsplit_complex (&all, fnargs);
|
||
|
||
VEC_free (tree, heap, fnargs);
|
||
|
||
/* Output all parameter conversion instructions (possibly including calls)
|
||
now that all parameters have been copied out of hard registers. */
|
||
emit_insn (all.first_conversion_insn);
|
||
|
||
/* Estimate reload stack alignment from scalar return mode. */
|
||
if (SUPPORTS_STACK_ALIGNMENT)
|
||
{
|
||
if (DECL_RESULT (fndecl))
|
||
{
|
||
tree type = TREE_TYPE (DECL_RESULT (fndecl));
|
||
enum machine_mode mode = TYPE_MODE (type);
|
||
|
||
if (mode != BLKmode
|
||
&& mode != VOIDmode
|
||
&& !AGGREGATE_TYPE_P (type))
|
||
{
|
||
unsigned int align = GET_MODE_ALIGNMENT (mode);
|
||
if (crtl->stack_alignment_estimated < align)
|
||
{
|
||
gcc_assert (!crtl->stack_realign_processed);
|
||
crtl->stack_alignment_estimated = align;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
/* If we are receiving a struct value address as the first argument, set up
|
||
the RTL for the function result. As this might require code to convert
|
||
the transmitted address to Pmode, we do this here to ensure that possible
|
||
preliminary conversions of the address have been emitted already. */
|
||
if (all.function_result_decl)
|
||
{
|
||
tree result = DECL_RESULT (current_function_decl);
|
||
rtx addr = DECL_RTL (all.function_result_decl);
|
||
rtx x;
|
||
|
||
if (DECL_BY_REFERENCE (result))
|
||
{
|
||
SET_DECL_VALUE_EXPR (result, all.function_result_decl);
|
||
x = addr;
|
||
}
|
||
else
|
||
{
|
||
SET_DECL_VALUE_EXPR (result,
|
||
build1 (INDIRECT_REF, TREE_TYPE (result),
|
||
all.function_result_decl));
|
||
addr = convert_memory_address (Pmode, addr);
|
||
x = gen_rtx_MEM (DECL_MODE (result), addr);
|
||
set_mem_attributes (x, result, 1);
|
||
}
|
||
|
||
DECL_HAS_VALUE_EXPR_P (result) = 1;
|
||
|
||
SET_DECL_RTL (result, x);
|
||
}
|
||
|
||
/* We have aligned all the args, so add space for the pretend args. */
|
||
crtl->args.pretend_args_size = all.pretend_args_size;
|
||
all.stack_args_size.constant += all.extra_pretend_bytes;
|
||
crtl->args.size = all.stack_args_size.constant;
|
||
|
||
/* Adjust function incoming argument size for alignment and
|
||
minimum length. */
|
||
|
||
#ifdef REG_PARM_STACK_SPACE
|
||
crtl->args.size = MAX (crtl->args.size,
|
||
REG_PARM_STACK_SPACE (fndecl));
|
||
#endif
|
||
|
||
crtl->args.size = CEIL_ROUND (crtl->args.size,
|
||
PARM_BOUNDARY / BITS_PER_UNIT);
|
||
|
||
#ifdef ARGS_GROW_DOWNWARD
|
||
crtl->args.arg_offset_rtx
|
||
= (all.stack_args_size.var == 0 ? GEN_INT (-all.stack_args_size.constant)
|
||
: expand_expr (size_diffop (all.stack_args_size.var,
|
||
size_int (-all.stack_args_size.constant)),
|
||
NULL_RTX, VOIDmode, EXPAND_NORMAL));
|
||
#else
|
||
crtl->args.arg_offset_rtx = ARGS_SIZE_RTX (all.stack_args_size);
|
||
#endif
|
||
|
||
/* See how many bytes, if any, of its args a function should try to pop
|
||
on return. */
|
||
|
||
crtl->args.pops_args = targetm.calls.return_pops_args (fndecl,
|
||
TREE_TYPE (fndecl),
|
||
crtl->args.size);
|
||
|
||
/* For stdarg.h function, save info about
|
||
regs and stack space used by the named args. */
|
||
|
||
crtl->args.info = all.args_so_far_v;
|
||
|
||
/* Set the rtx used for the function return value. Put this in its
|
||
own variable so any optimizers that need this information don't have
|
||
to include tree.h. Do this here so it gets done when an inlined
|
||
function gets output. */
|
||
|
||
crtl->return_rtx
|
||
= (DECL_RTL_SET_P (DECL_RESULT (fndecl))
|
||
? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
|
||
|
||
/* If scalar return value was computed in a pseudo-reg, or was a named
|
||
return value that got dumped to the stack, copy that to the hard
|
||
return register. */
|
||
if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
|
||
{
|
||
tree decl_result = DECL_RESULT (fndecl);
|
||
rtx decl_rtl = DECL_RTL (decl_result);
|
||
|
||
if (REG_P (decl_rtl)
|
||
? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
|
||
: DECL_REGISTER (decl_result))
|
||
{
|
||
rtx real_decl_rtl;
|
||
|
||
real_decl_rtl = targetm.calls.function_value (TREE_TYPE (decl_result),
|
||
fndecl, true);
|
||
REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
|
||
/* The delay slot scheduler assumes that crtl->return_rtx
|
||
holds the hard register containing the return value, not a
|
||
temporary pseudo. */
|
||
crtl->return_rtx = real_decl_rtl;
|
||
}
|
||
}
|
||
}
|
||
|
||
/* A subroutine of gimplify_parameters, invoked via walk_tree.
|
||
For all seen types, gimplify their sizes. */
|
||
|
||
static tree
|
||
gimplify_parm_type (tree *tp, int *walk_subtrees, void *data)
|
||
{
|
||
tree t = *tp;
|
||
|
||
*walk_subtrees = 0;
|
||
if (TYPE_P (t))
|
||
{
|
||
if (POINTER_TYPE_P (t))
|
||
*walk_subtrees = 1;
|
||
else if (TYPE_SIZE (t) && !TREE_CONSTANT (TYPE_SIZE (t))
|
||
&& !TYPE_SIZES_GIMPLIFIED (t))
|
||
{
|
||
gimplify_type_sizes (t, (gimple_seq *) data);
|
||
*walk_subtrees = 1;
|
||
}
|
||
}
|
||
|
||
return NULL;
|
||
}
|
||
|
||
/* Gimplify the parameter list for current_function_decl. This involves
|
||
evaluating SAVE_EXPRs of variable sized parameters and generating code
|
||
to implement callee-copies reference parameters. Returns a sequence of
|
||
statements to add to the beginning of the function. */
|
||
|
||
gimple_seq
|
||
gimplify_parameters (void)
|
||
{
|
||
struct assign_parm_data_all all;
|
||
tree parm;
|
||
gimple_seq stmts = NULL;
|
||
VEC(tree, heap) *fnargs;
|
||
unsigned i;
|
||
|
||
assign_parms_initialize_all (&all);
|
||
fnargs = assign_parms_augmented_arg_list (&all);
|
||
|
||
FOR_EACH_VEC_ELT (tree, fnargs, i, parm)
|
||
{
|
||
struct assign_parm_data_one data;
|
||
|
||
/* Extract the type of PARM; adjust it according to ABI. */
|
||
assign_parm_find_data_types (&all, parm, &data);
|
||
|
||
/* Early out for errors and void parameters. */
|
||
if (data.passed_mode == VOIDmode || DECL_SIZE (parm) == NULL)
|
||
continue;
|
||
|
||
/* Update info on where next arg arrives in registers. */
|
||
targetm.calls.function_arg_advance (all.args_so_far, data.promoted_mode,
|
||
data.passed_type, data.named_arg);
|
||
|
||
/* ??? Once upon a time variable_size stuffed parameter list
|
||
SAVE_EXPRs (amongst others) onto a pending sizes list. This
|
||
turned out to be less than manageable in the gimple world.
|
||
Now we have to hunt them down ourselves. */
|
||
walk_tree_without_duplicates (&data.passed_type,
|
||
gimplify_parm_type, &stmts);
|
||
|
||
if (TREE_CODE (DECL_SIZE_UNIT (parm)) != INTEGER_CST)
|
||
{
|
||
gimplify_one_sizepos (&DECL_SIZE (parm), &stmts);
|
||
gimplify_one_sizepos (&DECL_SIZE_UNIT (parm), &stmts);
|
||
}
|
||
|
||
if (data.passed_pointer)
|
||
{
|
||
tree type = TREE_TYPE (data.passed_type);
|
||
if (reference_callee_copied (&all.args_so_far_v, TYPE_MODE (type),
|
||
type, data.named_arg))
|
||
{
|
||
tree local, t;
|
||
|
||
/* For constant-sized objects, this is trivial; for
|
||
variable-sized objects, we have to play games. */
|
||
if (TREE_CODE (DECL_SIZE_UNIT (parm)) == INTEGER_CST
|
||
&& !(flag_stack_check == GENERIC_STACK_CHECK
|
||
&& compare_tree_int (DECL_SIZE_UNIT (parm),
|
||
STACK_CHECK_MAX_VAR_SIZE) > 0))
|
||
{
|
||
local = create_tmp_var (type, get_name (parm));
|
||
DECL_IGNORED_P (local) = 0;
|
||
/* If PARM was addressable, move that flag over
|
||
to the local copy, as its address will be taken,
|
||
not the PARMs. Keep the parms address taken
|
||
as we'll query that flag during gimplification. */
|
||
if (TREE_ADDRESSABLE (parm))
|
||
TREE_ADDRESSABLE (local) = 1;
|
||
else if (TREE_CODE (type) == COMPLEX_TYPE
|
||
|| TREE_CODE (type) == VECTOR_TYPE)
|
||
DECL_GIMPLE_REG_P (local) = 1;
|
||
}
|
||
else
|
||
{
|
||
tree ptr_type, addr;
|
||
|
||
ptr_type = build_pointer_type (type);
|
||
addr = create_tmp_reg (ptr_type, get_name (parm));
|
||
DECL_IGNORED_P (addr) = 0;
|
||
local = build_fold_indirect_ref (addr);
|
||
|
||
t = builtin_decl_explicit (BUILT_IN_ALLOCA_WITH_ALIGN);
|
||
t = build_call_expr (t, 2, DECL_SIZE_UNIT (parm),
|
||
size_int (DECL_ALIGN (parm)));
|
||
|
||
/* The call has been built for a variable-sized object. */
|
||
CALL_ALLOCA_FOR_VAR_P (t) = 1;
|
||
t = fold_convert (ptr_type, t);
|
||
t = build2 (MODIFY_EXPR, TREE_TYPE (addr), addr, t);
|
||
gimplify_and_add (t, &stmts);
|
||
}
|
||
|
||
gimplify_assign (local, parm, &stmts);
|
||
|
||
SET_DECL_VALUE_EXPR (parm, local);
|
||
DECL_HAS_VALUE_EXPR_P (parm) = 1;
|
||
}
|
||
}
|
||
}
|
||
|
||
VEC_free (tree, heap, fnargs);
|
||
|
||
return stmts;
|
||
}
|
||
|
||
/* Compute the size and offset from the start of the stacked arguments for a
|
||
parm passed in mode PASSED_MODE and with type TYPE.
|
||
|
||
INITIAL_OFFSET_PTR points to the current offset into the stacked
|
||
arguments.
|
||
|
||
The starting offset and size for this parm are returned in
|
||
LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
|
||
nonzero, the offset is that of stack slot, which is returned in
|
||
LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
|
||
padding required from the initial offset ptr to the stack slot.
|
||
|
||
IN_REGS is nonzero if the argument will be passed in registers. It will
|
||
never be set if REG_PARM_STACK_SPACE is not defined.
|
||
|
||
FNDECL is the function in which the argument was defined.
|
||
|
||
There are two types of rounding that are done. The first, controlled by
|
||
TARGET_FUNCTION_ARG_BOUNDARY, forces the offset from the start of the
|
||
argument list to be aligned to the specific boundary (in bits). This
|
||
rounding affects the initial and starting offsets, but not the argument
|
||
size.
|
||
|
||
The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
|
||
optionally rounds the size of the parm to PARM_BOUNDARY. The
|
||
initial offset is not affected by this rounding, while the size always
|
||
is and the starting offset may be. */
|
||
|
||
/* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
|
||
INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
|
||
callers pass in the total size of args so far as
|
||
INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
|
||
|
||
void
|
||
locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
|
||
int partial, tree fndecl ATTRIBUTE_UNUSED,
|
||
struct args_size *initial_offset_ptr,
|
||
struct locate_and_pad_arg_data *locate)
|
||
{
|
||
tree sizetree;
|
||
enum direction where_pad;
|
||
unsigned int boundary, round_boundary;
|
||
int reg_parm_stack_space = 0;
|
||
int part_size_in_regs;
|
||
|
||
#ifdef REG_PARM_STACK_SPACE
|
||
reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
|
||
|
||
/* If we have found a stack parm before we reach the end of the
|
||
area reserved for registers, skip that area. */
|
||
if (! in_regs)
|
||
{
|
||
if (reg_parm_stack_space > 0)
|
||
{
|
||
if (initial_offset_ptr->var)
|
||
{
|
||
initial_offset_ptr->var
|
||
= size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
|
||
ssize_int (reg_parm_stack_space));
|
||
initial_offset_ptr->constant = 0;
|
||
}
|
||
else if (initial_offset_ptr->constant < reg_parm_stack_space)
|
||
initial_offset_ptr->constant = reg_parm_stack_space;
|
||
}
|
||
}
|
||
#endif /* REG_PARM_STACK_SPACE */
|
||
|
||
part_size_in_regs = (reg_parm_stack_space == 0 ? partial : 0);
|
||
|
||
sizetree
|
||
= type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
|
||
where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
|
||
boundary = targetm.calls.function_arg_boundary (passed_mode, type);
|
||
round_boundary = targetm.calls.function_arg_round_boundary (passed_mode,
|
||
type);
|
||
locate->where_pad = where_pad;
|
||
|
||
/* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
|
||
if (boundary > MAX_SUPPORTED_STACK_ALIGNMENT)
|
||
boundary = MAX_SUPPORTED_STACK_ALIGNMENT;
|
||
|
||
locate->boundary = boundary;
|
||
|
||
if (SUPPORTS_STACK_ALIGNMENT)
|
||
{
|
||
/* stack_alignment_estimated can't change after stack has been
|
||
realigned. */
|
||
if (crtl->stack_alignment_estimated < boundary)
|
||
{
|
||
if (!crtl->stack_realign_processed)
|
||
crtl->stack_alignment_estimated = boundary;
|
||
else
|
||
{
|
||
/* If stack is realigned and stack alignment value
|
||
hasn't been finalized, it is OK not to increase
|
||
stack_alignment_estimated. The bigger alignment
|
||
requirement is recorded in stack_alignment_needed
|
||
below. */
|
||
gcc_assert (!crtl->stack_realign_finalized
|
||
&& crtl->stack_realign_needed);
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Remember if the outgoing parameter requires extra alignment on the
|
||
calling function side. */
|
||
if (crtl->stack_alignment_needed < boundary)
|
||
crtl->stack_alignment_needed = boundary;
|
||
if (crtl->preferred_stack_boundary < boundary)
|
||
crtl->preferred_stack_boundary = boundary;
|
||
|
||
#ifdef ARGS_GROW_DOWNWARD
|
||
locate->slot_offset.constant = -initial_offset_ptr->constant;
|
||
if (initial_offset_ptr->var)
|
||
locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
|
||
initial_offset_ptr->var);
|
||
|
||
{
|
||
tree s2 = sizetree;
|
||
if (where_pad != none
|
||
&& (!host_integerp (sizetree, 1)
|
||
|| (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % round_boundary))
|
||
s2 = round_up (s2, round_boundary / BITS_PER_UNIT);
|
||
SUB_PARM_SIZE (locate->slot_offset, s2);
|
||
}
|
||
|
||
locate->slot_offset.constant += part_size_in_regs;
|
||
|
||
if (!in_regs
|
||
#ifdef REG_PARM_STACK_SPACE
|
||
|| REG_PARM_STACK_SPACE (fndecl) > 0
|
||
#endif
|
||
)
|
||
pad_to_arg_alignment (&locate->slot_offset, boundary,
|
||
&locate->alignment_pad);
|
||
|
||
locate->size.constant = (-initial_offset_ptr->constant
|
||
- locate->slot_offset.constant);
|
||
if (initial_offset_ptr->var)
|
||
locate->size.var = size_binop (MINUS_EXPR,
|
||
size_binop (MINUS_EXPR,
|
||
ssize_int (0),
|
||
initial_offset_ptr->var),
|
||
locate->slot_offset.var);
|
||
|
||
/* Pad_below needs the pre-rounded size to know how much to pad
|
||
below. */
|
||
locate->offset = locate->slot_offset;
|
||
if (where_pad == downward)
|
||
pad_below (&locate->offset, passed_mode, sizetree);
|
||
|
||
#else /* !ARGS_GROW_DOWNWARD */
|
||
if (!in_regs
|
||
#ifdef REG_PARM_STACK_SPACE
|
||
|| REG_PARM_STACK_SPACE (fndecl) > 0
|
||
#endif
|
||
)
|
||
pad_to_arg_alignment (initial_offset_ptr, boundary,
|
||
&locate->alignment_pad);
|
||
locate->slot_offset = *initial_offset_ptr;
|
||
|
||
#ifdef PUSH_ROUNDING
|
||
if (passed_mode != BLKmode)
|
||
sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
|
||
#endif
|
||
|
||
/* Pad_below needs the pre-rounded size to know how much to pad below
|
||
so this must be done before rounding up. */
|
||
locate->offset = locate->slot_offset;
|
||
if (where_pad == downward)
|
||
pad_below (&locate->offset, passed_mode, sizetree);
|
||
|
||
if (where_pad != none
|
||
&& (!host_integerp (sizetree, 1)
|
||
|| (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % round_boundary))
|
||
sizetree = round_up (sizetree, round_boundary / BITS_PER_UNIT);
|
||
|
||
ADD_PARM_SIZE (locate->size, sizetree);
|
||
|
||
locate->size.constant -= part_size_in_regs;
|
||
#endif /* ARGS_GROW_DOWNWARD */
|
||
|
||
#ifdef FUNCTION_ARG_OFFSET
|
||
locate->offset.constant += FUNCTION_ARG_OFFSET (passed_mode, type);
|
||
#endif
|
||
}
|
||
|
||
/* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
|
||
BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
|
||
|
||
static void
|
||
pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
|
||
struct args_size *alignment_pad)
|
||
{
|
||
tree save_var = NULL_TREE;
|
||
HOST_WIDE_INT save_constant = 0;
|
||
int boundary_in_bytes = boundary / BITS_PER_UNIT;
|
||
HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
|
||
|
||
#ifdef SPARC_STACK_BOUNDARY_HACK
|
||
/* ??? The SPARC port may claim a STACK_BOUNDARY higher than
|
||
the real alignment of %sp. However, when it does this, the
|
||
alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
|
||
if (SPARC_STACK_BOUNDARY_HACK)
|
||
sp_offset = 0;
|
||
#endif
|
||
|
||
if (boundary > PARM_BOUNDARY)
|
||
{
|
||
save_var = offset_ptr->var;
|
||
save_constant = offset_ptr->constant;
|
||
}
|
||
|
||
alignment_pad->var = NULL_TREE;
|
||
alignment_pad->constant = 0;
|
||
|
||
if (boundary > BITS_PER_UNIT)
|
||
{
|
||
if (offset_ptr->var)
|
||
{
|
||
tree sp_offset_tree = ssize_int (sp_offset);
|
||
tree offset = size_binop (PLUS_EXPR,
|
||
ARGS_SIZE_TREE (*offset_ptr),
|
||
sp_offset_tree);
|
||
#ifdef ARGS_GROW_DOWNWARD
|
||
tree rounded = round_down (offset, boundary / BITS_PER_UNIT);
|
||
#else
|
||
tree rounded = round_up (offset, boundary / BITS_PER_UNIT);
|
||
#endif
|
||
|
||
offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
|
||
/* ARGS_SIZE_TREE includes constant term. */
|
||
offset_ptr->constant = 0;
|
||
if (boundary > PARM_BOUNDARY)
|
||
alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
|
||
save_var);
|
||
}
|
||
else
|
||
{
|
||
offset_ptr->constant = -sp_offset +
|
||
#ifdef ARGS_GROW_DOWNWARD
|
||
FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
|
||
#else
|
||
CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
|
||
#endif
|
||
if (boundary > PARM_BOUNDARY)
|
||
alignment_pad->constant = offset_ptr->constant - save_constant;
|
||
}
|
||
}
|
||
}
|
||
|
||
static void
|
||
pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree)
|
||
{
|
||
if (passed_mode != BLKmode)
|
||
{
|
||
if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
|
||
offset_ptr->constant
|
||
+= (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
|
||
/ PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
|
||
- GET_MODE_SIZE (passed_mode));
|
||
}
|
||
else
|
||
{
|
||
if (TREE_CODE (sizetree) != INTEGER_CST
|
||
|| (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
|
||
{
|
||
/* Round the size up to multiple of PARM_BOUNDARY bits. */
|
||
tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
|
||
/* Add it in. */
|
||
ADD_PARM_SIZE (*offset_ptr, s2);
|
||
SUB_PARM_SIZE (*offset_ptr, sizetree);
|
||
}
|
||
}
|
||
}
|
||
|
||
|
||
/* True if register REGNO was alive at a place where `setjmp' was
|
||
called and was set more than once or is an argument. Such regs may
|
||
be clobbered by `longjmp'. */
|
||
|
||
static bool
|
||
regno_clobbered_at_setjmp (bitmap setjmp_crosses, int regno)
|
||
{
|
||
/* There appear to be cases where some local vars never reach the
|
||
backend but have bogus regnos. */
|
||
if (regno >= max_reg_num ())
|
||
return false;
|
||
|
||
return ((REG_N_SETS (regno) > 1
|
||
|| REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR), regno))
|
||
&& REGNO_REG_SET_P (setjmp_crosses, regno));
|
||
}
|
||
|
||
/* Walk the tree of blocks describing the binding levels within a
|
||
function and warn about variables the might be killed by setjmp or
|
||
vfork. This is done after calling flow_analysis before register
|
||
allocation since that will clobber the pseudo-regs to hard
|
||
regs. */
|
||
|
||
static void
|
||
setjmp_vars_warning (bitmap setjmp_crosses, tree block)
|
||
{
|
||
tree decl, sub;
|
||
|
||
for (decl = BLOCK_VARS (block); decl; decl = DECL_CHAIN (decl))
|
||
{
|
||
if (TREE_CODE (decl) == VAR_DECL
|
||
&& DECL_RTL_SET_P (decl)
|
||
&& REG_P (DECL_RTL (decl))
|
||
&& regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
|
||
warning (OPT_Wclobbered, "variable %q+D might be clobbered by"
|
||
" %<longjmp%> or %<vfork%>", decl);
|
||
}
|
||
|
||
for (sub = BLOCK_SUBBLOCKS (block); sub; sub = BLOCK_CHAIN (sub))
|
||
setjmp_vars_warning (setjmp_crosses, sub);
|
||
}
|
||
|
||
/* Do the appropriate part of setjmp_vars_warning
|
||
but for arguments instead of local variables. */
|
||
|
||
static void
|
||
setjmp_args_warning (bitmap setjmp_crosses)
|
||
{
|
||
tree decl;
|
||
for (decl = DECL_ARGUMENTS (current_function_decl);
|
||
decl; decl = DECL_CHAIN (decl))
|
||
if (DECL_RTL (decl) != 0
|
||
&& REG_P (DECL_RTL (decl))
|
||
&& regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
|
||
warning (OPT_Wclobbered,
|
||
"argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
|
||
decl);
|
||
}
|
||
|
||
/* Generate warning messages for variables live across setjmp. */
|
||
|
||
void
|
||
generate_setjmp_warnings (void)
|
||
{
|
||
bitmap setjmp_crosses = regstat_get_setjmp_crosses ();
|
||
|
||
if (n_basic_blocks == NUM_FIXED_BLOCKS
|
||
|| bitmap_empty_p (setjmp_crosses))
|
||
return;
|
||
|
||
setjmp_vars_warning (setjmp_crosses, DECL_INITIAL (current_function_decl));
|
||
setjmp_args_warning (setjmp_crosses);
|
||
}
|
||
|
||
|
||
/* Reverse the order of elements in the fragment chain T of blocks,
|
||
and return the new head of the chain (old last element).
|
||
In addition to that clear BLOCK_SAME_RANGE flags when needed
|
||
and adjust BLOCK_SUPERCONTEXT from the super fragment to
|
||
its super fragment origin. */
|
||
|
||
static tree
|
||
block_fragments_nreverse (tree t)
|
||
{
|
||
tree prev = 0, block, next, prev_super = 0;
|
||
tree super = BLOCK_SUPERCONTEXT (t);
|
||
if (BLOCK_FRAGMENT_ORIGIN (super))
|
||
super = BLOCK_FRAGMENT_ORIGIN (super);
|
||
for (block = t; block; block = next)
|
||
{
|
||
next = BLOCK_FRAGMENT_CHAIN (block);
|
||
BLOCK_FRAGMENT_CHAIN (block) = prev;
|
||
if ((prev && !BLOCK_SAME_RANGE (prev))
|
||
|| (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (block))
|
||
!= prev_super))
|
||
BLOCK_SAME_RANGE (block) = 0;
|
||
prev_super = BLOCK_SUPERCONTEXT (block);
|
||
BLOCK_SUPERCONTEXT (block) = super;
|
||
prev = block;
|
||
}
|
||
t = BLOCK_FRAGMENT_ORIGIN (t);
|
||
if (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (t))
|
||
!= prev_super)
|
||
BLOCK_SAME_RANGE (t) = 0;
|
||
BLOCK_SUPERCONTEXT (t) = super;
|
||
return prev;
|
||
}
|
||
|
||
/* Reverse the order of elements in the chain T of blocks,
|
||
and return the new head of the chain (old last element).
|
||
Also do the same on subblocks and reverse the order of elements
|
||
in BLOCK_FRAGMENT_CHAIN as well. */
|
||
|
||
static tree
|
||
blocks_nreverse_all (tree t)
|
||
{
|
||
tree prev = 0, block, next;
|
||
for (block = t; block; block = next)
|
||
{
|
||
next = BLOCK_CHAIN (block);
|
||
BLOCK_CHAIN (block) = prev;
|
||
if (BLOCK_FRAGMENT_CHAIN (block)
|
||
&& BLOCK_FRAGMENT_ORIGIN (block) == NULL_TREE)
|
||
{
|
||
BLOCK_FRAGMENT_CHAIN (block)
|
||
= block_fragments_nreverse (BLOCK_FRAGMENT_CHAIN (block));
|
||
if (!BLOCK_SAME_RANGE (BLOCK_FRAGMENT_CHAIN (block)))
|
||
BLOCK_SAME_RANGE (block) = 0;
|
||
}
|
||
BLOCK_SUBBLOCKS (block) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block));
|
||
prev = block;
|
||
}
|
||
return prev;
|
||
}
|
||
|
||
|
||
/* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
|
||
and create duplicate blocks. */
|
||
/* ??? Need an option to either create block fragments or to create
|
||
abstract origin duplicates of a source block. It really depends
|
||
on what optimization has been performed. */
|
||
|
||
void
|
||
reorder_blocks (void)
|
||
{
|
||
tree block = DECL_INITIAL (current_function_decl);
|
||
VEC(tree,heap) *block_stack;
|
||
|
||
if (block == NULL_TREE)
|
||
return;
|
||
|
||
block_stack = VEC_alloc (tree, heap, 10);
|
||
|
||
/* Reset the TREE_ASM_WRITTEN bit for all blocks. */
|
||
clear_block_marks (block);
|
||
|
||
/* Prune the old trees away, so that they don't get in the way. */
|
||
BLOCK_SUBBLOCKS (block) = NULL_TREE;
|
||
BLOCK_CHAIN (block) = NULL_TREE;
|
||
|
||
/* Recreate the block tree from the note nesting. */
|
||
reorder_blocks_1 (get_insns (), block, &block_stack);
|
||
BLOCK_SUBBLOCKS (block) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block));
|
||
|
||
VEC_free (tree, heap, block_stack);
|
||
}
|
||
|
||
/* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
|
||
|
||
void
|
||
clear_block_marks (tree block)
|
||
{
|
||
while (block)
|
||
{
|
||
TREE_ASM_WRITTEN (block) = 0;
|
||
clear_block_marks (BLOCK_SUBBLOCKS (block));
|
||
block = BLOCK_CHAIN (block);
|
||
}
|
||
}
|
||
|
||
static void
|
||
reorder_blocks_1 (rtx insns, tree current_block, VEC(tree,heap) **p_block_stack)
|
||
{
|
||
rtx insn;
|
||
tree prev_beg = NULL_TREE, prev_end = NULL_TREE;
|
||
|
||
for (insn = insns; insn; insn = NEXT_INSN (insn))
|
||
{
|
||
if (NOTE_P (insn))
|
||
{
|
||
if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_BEG)
|
||
{
|
||
tree block = NOTE_BLOCK (insn);
|
||
tree origin;
|
||
|
||
gcc_assert (BLOCK_FRAGMENT_ORIGIN (block) == NULL_TREE);
|
||
origin = block;
|
||
|
||
if (prev_end)
|
||
BLOCK_SAME_RANGE (prev_end) = 0;
|
||
prev_end = NULL_TREE;
|
||
|
||
/* If we have seen this block before, that means it now
|
||
spans multiple address regions. Create a new fragment. */
|
||
if (TREE_ASM_WRITTEN (block))
|
||
{
|
||
tree new_block = copy_node (block);
|
||
|
||
BLOCK_SAME_RANGE (new_block) = 0;
|
||
BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
|
||
BLOCK_FRAGMENT_CHAIN (new_block)
|
||
= BLOCK_FRAGMENT_CHAIN (origin);
|
||
BLOCK_FRAGMENT_CHAIN (origin) = new_block;
|
||
|
||
NOTE_BLOCK (insn) = new_block;
|
||
block = new_block;
|
||
}
|
||
|
||
if (prev_beg == current_block && prev_beg)
|
||
BLOCK_SAME_RANGE (block) = 1;
|
||
|
||
prev_beg = origin;
|
||
|
||
BLOCK_SUBBLOCKS (block) = 0;
|
||
TREE_ASM_WRITTEN (block) = 1;
|
||
/* When there's only one block for the entire function,
|
||
current_block == block and we mustn't do this, it
|
||
will cause infinite recursion. */
|
||
if (block != current_block)
|
||
{
|
||
tree super;
|
||
if (block != origin)
|
||
gcc_assert (BLOCK_SUPERCONTEXT (origin) == current_block
|
||
|| BLOCK_FRAGMENT_ORIGIN (BLOCK_SUPERCONTEXT
|
||
(origin))
|
||
== current_block);
|
||
if (VEC_empty (tree, *p_block_stack))
|
||
super = current_block;
|
||
else
|
||
{
|
||
super = VEC_last (tree, *p_block_stack);
|
||
gcc_assert (super == current_block
|
||
|| BLOCK_FRAGMENT_ORIGIN (super)
|
||
== current_block);
|
||
}
|
||
BLOCK_SUPERCONTEXT (block) = super;
|
||
BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
|
||
BLOCK_SUBBLOCKS (current_block) = block;
|
||
current_block = origin;
|
||
}
|
||
VEC_safe_push (tree, heap, *p_block_stack, block);
|
||
}
|
||
else if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_END)
|
||
{
|
||
NOTE_BLOCK (insn) = VEC_pop (tree, *p_block_stack);
|
||
current_block = BLOCK_SUPERCONTEXT (current_block);
|
||
if (BLOCK_FRAGMENT_ORIGIN (current_block))
|
||
current_block = BLOCK_FRAGMENT_ORIGIN (current_block);
|
||
prev_beg = NULL_TREE;
|
||
prev_end = BLOCK_SAME_RANGE (NOTE_BLOCK (insn))
|
||
? NOTE_BLOCK (insn) : NULL_TREE;
|
||
}
|
||
}
|
||
else
|
||
{
|
||
prev_beg = NULL_TREE;
|
||
if (prev_end)
|
||
BLOCK_SAME_RANGE (prev_end) = 0;
|
||
prev_end = NULL_TREE;
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Reverse the order of elements in the chain T of blocks,
|
||
and return the new head of the chain (old last element). */
|
||
|
||
tree
|
||
blocks_nreverse (tree t)
|
||
{
|
||
tree prev = 0, block, next;
|
||
for (block = t; block; block = next)
|
||
{
|
||
next = BLOCK_CHAIN (block);
|
||
BLOCK_CHAIN (block) = prev;
|
||
prev = block;
|
||
}
|
||
return prev;
|
||
}
|
||
|
||
/* Concatenate two chains of blocks (chained through BLOCK_CHAIN)
|
||
by modifying the last node in chain 1 to point to chain 2. */
|
||
|
||
tree
|
||
block_chainon (tree op1, tree op2)
|
||
{
|
||
tree t1;
|
||
|
||
if (!op1)
|
||
return op2;
|
||
if (!op2)
|
||
return op1;
|
||
|
||
for (t1 = op1; BLOCK_CHAIN (t1); t1 = BLOCK_CHAIN (t1))
|
||
continue;
|
||
BLOCK_CHAIN (t1) = op2;
|
||
|
||
#ifdef ENABLE_TREE_CHECKING
|
||
{
|
||
tree t2;
|
||
for (t2 = op2; t2; t2 = BLOCK_CHAIN (t2))
|
||
gcc_assert (t2 != t1);
|
||
}
|
||
#endif
|
||
|
||
return op1;
|
||
}
|
||
|
||
/* Count the subblocks of the list starting with BLOCK. If VECTOR is
|
||
non-NULL, list them all into VECTOR, in a depth-first preorder
|
||
traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
|
||
blocks. */
|
||
|
||
static int
|
||
all_blocks (tree block, tree *vector)
|
||
{
|
||
int n_blocks = 0;
|
||
|
||
while (block)
|
||
{
|
||
TREE_ASM_WRITTEN (block) = 0;
|
||
|
||
/* Record this block. */
|
||
if (vector)
|
||
vector[n_blocks] = block;
|
||
|
||
++n_blocks;
|
||
|
||
/* Record the subblocks, and their subblocks... */
|
||
n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
|
||
vector ? vector + n_blocks : 0);
|
||
block = BLOCK_CHAIN (block);
|
||
}
|
||
|
||
return n_blocks;
|
||
}
|
||
|
||
/* Return a vector containing all the blocks rooted at BLOCK. The
|
||
number of elements in the vector is stored in N_BLOCKS_P. The
|
||
vector is dynamically allocated; it is the caller's responsibility
|
||
to call `free' on the pointer returned. */
|
||
|
||
static tree *
|
||
get_block_vector (tree block, int *n_blocks_p)
|
||
{
|
||
tree *block_vector;
|
||
|
||
*n_blocks_p = all_blocks (block, NULL);
|
||
block_vector = XNEWVEC (tree, *n_blocks_p);
|
||
all_blocks (block, block_vector);
|
||
|
||
return block_vector;
|
||
}
|
||
|
||
static GTY(()) int next_block_index = 2;
|
||
|
||
/* Set BLOCK_NUMBER for all the blocks in FN. */
|
||
|
||
void
|
||
number_blocks (tree fn)
|
||
{
|
||
int i;
|
||
int n_blocks;
|
||
tree *block_vector;
|
||
|
||
/* For SDB and XCOFF debugging output, we start numbering the blocks
|
||
from 1 within each function, rather than keeping a running
|
||
count. */
|
||
#if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
|
||
if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
|
||
next_block_index = 1;
|
||
#endif
|
||
|
||
block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
|
||
|
||
/* The top-level BLOCK isn't numbered at all. */
|
||
for (i = 1; i < n_blocks; ++i)
|
||
/* We number the blocks from two. */
|
||
BLOCK_NUMBER (block_vector[i]) = next_block_index++;
|
||
|
||
free (block_vector);
|
||
|
||
return;
|
||
}
|
||
|
||
/* If VAR is present in a subblock of BLOCK, return the subblock. */
|
||
|
||
DEBUG_FUNCTION tree
|
||
debug_find_var_in_block_tree (tree var, tree block)
|
||
{
|
||
tree t;
|
||
|
||
for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
|
||
if (t == var)
|
||
return block;
|
||
|
||
for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
|
||
{
|
||
tree ret = debug_find_var_in_block_tree (var, t);
|
||
if (ret)
|
||
return ret;
|
||
}
|
||
|
||
return NULL_TREE;
|
||
}
|
||
|
||
/* Keep track of whether we're in a dummy function context. If we are,
|
||
we don't want to invoke the set_current_function hook, because we'll
|
||
get into trouble if the hook calls target_reinit () recursively or
|
||
when the initial initialization is not yet complete. */
|
||
|
||
static bool in_dummy_function;
|
||
|
||
/* Invoke the target hook when setting cfun. Update the optimization options
|
||
if the function uses different options than the default. */
|
||
|
||
static void
|
||
invoke_set_current_function_hook (tree fndecl)
|
||
{
|
||
if (!in_dummy_function)
|
||
{
|
||
tree opts = ((fndecl)
|
||
? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl)
|
||
: optimization_default_node);
|
||
|
||
if (!opts)
|
||
opts = optimization_default_node;
|
||
|
||
/* Change optimization options if needed. */
|
||
if (optimization_current_node != opts)
|
||
{
|
||
optimization_current_node = opts;
|
||
cl_optimization_restore (&global_options, TREE_OPTIMIZATION (opts));
|
||
}
|
||
|
||
targetm.set_current_function (fndecl);
|
||
}
|
||
}
|
||
|
||
/* cfun should never be set directly; use this function. */
|
||
|
||
void
|
||
set_cfun (struct function *new_cfun)
|
||
{
|
||
if (cfun != new_cfun)
|
||
{
|
||
cfun = new_cfun;
|
||
invoke_set_current_function_hook (new_cfun ? new_cfun->decl : NULL_TREE);
|
||
}
|
||
}
|
||
|
||
/* Initialized with NOGC, making this poisonous to the garbage collector. */
|
||
|
||
static VEC(function_p,heap) *cfun_stack;
|
||
|
||
/* Push the current cfun onto the stack, and set cfun to new_cfun. */
|
||
|
||
void
|
||
push_cfun (struct function *new_cfun)
|
||
{
|
||
VEC_safe_push (function_p, heap, cfun_stack, cfun);
|
||
set_cfun (new_cfun);
|
||
}
|
||
|
||
/* Pop cfun from the stack. */
|
||
|
||
void
|
||
pop_cfun (void)
|
||
{
|
||
struct function *new_cfun = VEC_pop (function_p, cfun_stack);
|
||
set_cfun (new_cfun);
|
||
}
|
||
|
||
/* Return value of funcdef and increase it. */
|
||
int
|
||
get_next_funcdef_no (void)
|
||
{
|
||
return funcdef_no++;
|
||
}
|
||
|
||
/* Return value of funcdef. */
|
||
int
|
||
get_last_funcdef_no (void)
|
||
{
|
||
return funcdef_no;
|
||
}
|
||
|
||
/* Allocate a function structure for FNDECL and set its contents
|
||
to the defaults. Set cfun to the newly-allocated object.
|
||
Some of the helper functions invoked during initialization assume
|
||
that cfun has already been set. Therefore, assign the new object
|
||
directly into cfun and invoke the back end hook explicitly at the
|
||
very end, rather than initializing a temporary and calling set_cfun
|
||
on it.
|
||
|
||
ABSTRACT_P is true if this is a function that will never be seen by
|
||
the middle-end. Such functions are front-end concepts (like C++
|
||
function templates) that do not correspond directly to functions
|
||
placed in object files. */
|
||
|
||
void
|
||
allocate_struct_function (tree fndecl, bool abstract_p)
|
||
{
|
||
tree result;
|
||
tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE;
|
||
|
||
cfun = ggc_alloc_cleared_function ();
|
||
|
||
init_eh_for_function ();
|
||
|
||
if (init_machine_status)
|
||
cfun->machine = (*init_machine_status) ();
|
||
|
||
#ifdef OVERRIDE_ABI_FORMAT
|
||
OVERRIDE_ABI_FORMAT (fndecl);
|
||
#endif
|
||
|
||
invoke_set_current_function_hook (fndecl);
|
||
|
||
if (fndecl != NULL_TREE)
|
||
{
|
||
DECL_STRUCT_FUNCTION (fndecl) = cfun;
|
||
cfun->decl = fndecl;
|
||
current_function_funcdef_no = get_next_funcdef_no ();
|
||
|
||
result = DECL_RESULT (fndecl);
|
||
if (!abstract_p && aggregate_value_p (result, fndecl))
|
||
{
|
||
#ifdef PCC_STATIC_STRUCT_RETURN
|
||
cfun->returns_pcc_struct = 1;
|
||
#endif
|
||
cfun->returns_struct = 1;
|
||
}
|
||
|
||
cfun->stdarg = stdarg_p (fntype);
|
||
|
||
/* Assume all registers in stdarg functions need to be saved. */
|
||
cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE;
|
||
cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE;
|
||
|
||
/* ??? This could be set on a per-function basis by the front-end
|
||
but is this worth the hassle? */
|
||
cfun->can_throw_non_call_exceptions = flag_non_call_exceptions;
|
||
}
|
||
}
|
||
|
||
/* This is like allocate_struct_function, but pushes a new cfun for FNDECL
|
||
instead of just setting it. */
|
||
|
||
void
|
||
push_struct_function (tree fndecl)
|
||
{
|
||
VEC_safe_push (function_p, heap, cfun_stack, cfun);
|
||
allocate_struct_function (fndecl, false);
|
||
}
|
||
|
||
/* Reset crtl and other non-struct-function variables to defaults as
|
||
appropriate for emitting rtl at the start of a function. */
|
||
|
||
static void
|
||
prepare_function_start (void)
|
||
{
|
||
gcc_assert (!crtl->emit.x_last_insn);
|
||
init_temp_slots ();
|
||
init_emit ();
|
||
init_varasm_status ();
|
||
init_expr ();
|
||
default_rtl_profile ();
|
||
|
||
if (flag_stack_usage_info)
|
||
{
|
||
cfun->su = ggc_alloc_cleared_stack_usage ();
|
||
cfun->su->static_stack_size = -1;
|
||
}
|
||
|
||
cse_not_expected = ! optimize;
|
||
|
||
/* Caller save not needed yet. */
|
||
caller_save_needed = 0;
|
||
|
||
/* We haven't done register allocation yet. */
|
||
reg_renumber = 0;
|
||
|
||
/* Indicate that we have not instantiated virtual registers yet. */
|
||
virtuals_instantiated = 0;
|
||
|
||
/* Indicate that we want CONCATs now. */
|
||
generating_concat_p = 1;
|
||
|
||
/* Indicate we have no need of a frame pointer yet. */
|
||
frame_pointer_needed = 0;
|
||
}
|
||
|
||
/* Initialize the rtl expansion mechanism so that we can do simple things
|
||
like generate sequences. This is used to provide a context during global
|
||
initialization of some passes. You must call expand_dummy_function_end
|
||
to exit this context. */
|
||
|
||
void
|
||
init_dummy_function_start (void)
|
||
{
|
||
gcc_assert (!in_dummy_function);
|
||
in_dummy_function = true;
|
||
push_struct_function (NULL_TREE);
|
||
prepare_function_start ();
|
||
}
|
||
|
||
/* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
|
||
and initialize static variables for generating RTL for the statements
|
||
of the function. */
|
||
|
||
void
|
||
init_function_start (tree subr)
|
||
{
|
||
if (subr && DECL_STRUCT_FUNCTION (subr))
|
||
set_cfun (DECL_STRUCT_FUNCTION (subr));
|
||
else
|
||
allocate_struct_function (subr, false);
|
||
prepare_function_start ();
|
||
decide_function_section (subr);
|
||
|
||
/* Warn if this value is an aggregate type,
|
||
regardless of which calling convention we are using for it. */
|
||
if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
|
||
warning (OPT_Waggregate_return, "function returns an aggregate");
|
||
}
|
||
|
||
|
||
void
|
||
expand_main_function (void)
|
||
{
|
||
#if (defined(INVOKE__main) \
|
||
|| (!defined(HAS_INIT_SECTION) \
|
||
&& !defined(INIT_SECTION_ASM_OP) \
|
||
&& !defined(INIT_ARRAY_SECTION_ASM_OP)))
|
||
emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
|
||
#endif
|
||
}
|
||
|
||
/* Expand code to initialize the stack_protect_guard. This is invoked at
|
||
the beginning of a function to be protected. */
|
||
|
||
#ifndef HAVE_stack_protect_set
|
||
# define HAVE_stack_protect_set 0
|
||
# define gen_stack_protect_set(x,y) (gcc_unreachable (), NULL_RTX)
|
||
#endif
|
||
|
||
void
|
||
stack_protect_prologue (void)
|
||
{
|
||
tree guard_decl = targetm.stack_protect_guard ();
|
||
rtx x, y;
|
||
|
||
x = expand_normal (crtl->stack_protect_guard);
|
||
y = expand_normal (guard_decl);
|
||
|
||
/* Allow the target to copy from Y to X without leaking Y into a
|
||
register. */
|
||
if (HAVE_stack_protect_set)
|
||
{
|
||
rtx insn = gen_stack_protect_set (x, y);
|
||
if (insn)
|
||
{
|
||
emit_insn (insn);
|
||
return;
|
||
}
|
||
}
|
||
|
||
/* Otherwise do a straight move. */
|
||
emit_move_insn (x, y);
|
||
}
|
||
|
||
/* Expand code to verify the stack_protect_guard. This is invoked at
|
||
the end of a function to be protected. */
|
||
|
||
#ifndef HAVE_stack_protect_test
|
||
# define HAVE_stack_protect_test 0
|
||
# define gen_stack_protect_test(x, y, z) (gcc_unreachable (), NULL_RTX)
|
||
#endif
|
||
|
||
void
|
||
stack_protect_epilogue (void)
|
||
{
|
||
tree guard_decl = targetm.stack_protect_guard ();
|
||
rtx label = gen_label_rtx ();
|
||
rtx x, y, tmp;
|
||
|
||
x = expand_normal (crtl->stack_protect_guard);
|
||
y = expand_normal (guard_decl);
|
||
|
||
/* Allow the target to compare Y with X without leaking either into
|
||
a register. */
|
||
switch (HAVE_stack_protect_test != 0)
|
||
{
|
||
case 1:
|
||
tmp = gen_stack_protect_test (x, y, label);
|
||
if (tmp)
|
||
{
|
||
emit_insn (tmp);
|
||
break;
|
||
}
|
||
/* FALLTHRU */
|
||
|
||
default:
|
||
emit_cmp_and_jump_insns (x, y, EQ, NULL_RTX, ptr_mode, 1, label);
|
||
break;
|
||
}
|
||
|
||
/* The noreturn predictor has been moved to the tree level. The rtl-level
|
||
predictors estimate this branch about 20%, which isn't enough to get
|
||
things moved out of line. Since this is the only extant case of adding
|
||
a noreturn function at the rtl level, it doesn't seem worth doing ought
|
||
except adding the prediction by hand. */
|
||
tmp = get_last_insn ();
|
||
if (JUMP_P (tmp))
|
||
predict_insn_def (tmp, PRED_NORETURN, TAKEN);
|
||
|
||
expand_call (targetm.stack_protect_fail (), NULL_RTX, /*ignore=*/true);
|
||
free_temp_slots ();
|
||
emit_label (label);
|
||
}
|
||
|
||
/* Start the RTL for a new function, and set variables used for
|
||
emitting RTL.
|
||
SUBR is the FUNCTION_DECL node.
|
||
PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
|
||
the function's parameters, which must be run at any return statement. */
|
||
|
||
void
|
||
expand_function_start (tree subr)
|
||
{
|
||
/* Make sure volatile mem refs aren't considered
|
||
valid operands of arithmetic insns. */
|
||
init_recog_no_volatile ();
|
||
|
||
crtl->profile
|
||
= (profile_flag
|
||
&& ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
|
||
|
||
crtl->limit_stack
|
||
= (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
|
||
|
||
/* Make the label for return statements to jump to. Do not special
|
||
case machines with special return instructions -- they will be
|
||
handled later during jump, ifcvt, or epilogue creation. */
|
||
return_label = gen_label_rtx ();
|
||
|
||
/* Initialize rtx used to return the value. */
|
||
/* Do this before assign_parms so that we copy the struct value address
|
||
before any library calls that assign parms might generate. */
|
||
|
||
/* Decide whether to return the value in memory or in a register. */
|
||
if (aggregate_value_p (DECL_RESULT (subr), subr))
|
||
{
|
||
/* Returning something that won't go in a register. */
|
||
rtx value_address = 0;
|
||
|
||
#ifdef PCC_STATIC_STRUCT_RETURN
|
||
if (cfun->returns_pcc_struct)
|
||
{
|
||
int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
|
||
value_address = assemble_static_space (size);
|
||
}
|
||
else
|
||
#endif
|
||
{
|
||
rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 2);
|
||
/* Expect to be passed the address of a place to store the value.
|
||
If it is passed as an argument, assign_parms will take care of
|
||
it. */
|
||
if (sv)
|
||
{
|
||
value_address = gen_reg_rtx (Pmode);
|
||
emit_move_insn (value_address, sv);
|
||
}
|
||
}
|
||
if (value_address)
|
||
{
|
||
rtx x = value_address;
|
||
if (!DECL_BY_REFERENCE (DECL_RESULT (subr)))
|
||
{
|
||
x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), x);
|
||
set_mem_attributes (x, DECL_RESULT (subr), 1);
|
||
}
|
||
SET_DECL_RTL (DECL_RESULT (subr), x);
|
||
}
|
||
}
|
||
else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
|
||
/* If return mode is void, this decl rtl should not be used. */
|
||
SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
|
||
else
|
||
{
|
||
/* Compute the return values into a pseudo reg, which we will copy
|
||
into the true return register after the cleanups are done. */
|
||
tree return_type = TREE_TYPE (DECL_RESULT (subr));
|
||
if (TYPE_MODE (return_type) != BLKmode
|
||
&& targetm.calls.return_in_msb (return_type))
|
||
/* expand_function_end will insert the appropriate padding in
|
||
this case. Use the return value's natural (unpadded) mode
|
||
within the function proper. */
|
||
SET_DECL_RTL (DECL_RESULT (subr),
|
||
gen_reg_rtx (TYPE_MODE (return_type)));
|
||
else
|
||
{
|
||
/* In order to figure out what mode to use for the pseudo, we
|
||
figure out what the mode of the eventual return register will
|
||
actually be, and use that. */
|
||
rtx hard_reg = hard_function_value (return_type, subr, 0, 1);
|
||
|
||
/* Structures that are returned in registers are not
|
||
aggregate_value_p, so we may see a PARALLEL or a REG. */
|
||
if (REG_P (hard_reg))
|
||
SET_DECL_RTL (DECL_RESULT (subr),
|
||
gen_reg_rtx (GET_MODE (hard_reg)));
|
||
else
|
||
{
|
||
gcc_assert (GET_CODE (hard_reg) == PARALLEL);
|
||
SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
|
||
}
|
||
}
|
||
|
||
/* Set DECL_REGISTER flag so that expand_function_end will copy the
|
||
result to the real return register(s). */
|
||
DECL_REGISTER (DECL_RESULT (subr)) = 1;
|
||
}
|
||
|
||
/* Initialize rtx for parameters and local variables.
|
||
In some cases this requires emitting insns. */
|
||
assign_parms (subr);
|
||
|
||
/* If function gets a static chain arg, store it. */
|
||
if (cfun->static_chain_decl)
|
||
{
|
||
tree parm = cfun->static_chain_decl;
|
||
rtx local, chain, insn;
|
||
|
||
local = gen_reg_rtx (Pmode);
|
||
chain = targetm.calls.static_chain (current_function_decl, true);
|
||
|
||
set_decl_incoming_rtl (parm, chain, false);
|
||
SET_DECL_RTL (parm, local);
|
||
mark_reg_pointer (local, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
|
||
|
||
insn = emit_move_insn (local, chain);
|
||
|
||
/* Mark the register as eliminable, similar to parameters. */
|
||
if (MEM_P (chain)
|
||
&& reg_mentioned_p (arg_pointer_rtx, XEXP (chain, 0)))
|
||
set_dst_reg_note (insn, REG_EQUIV, chain, local);
|
||
}
|
||
|
||
/* If the function receives a non-local goto, then store the
|
||
bits we need to restore the frame pointer. */
|
||
if (cfun->nonlocal_goto_save_area)
|
||
{
|
||
tree t_save;
|
||
rtx r_save;
|
||
|
||
tree var = TREE_OPERAND (cfun->nonlocal_goto_save_area, 0);
|
||
gcc_assert (DECL_RTL_SET_P (var));
|
||
|
||
t_save = build4 (ARRAY_REF,
|
||
TREE_TYPE (TREE_TYPE (cfun->nonlocal_goto_save_area)),
|
||
cfun->nonlocal_goto_save_area,
|
||
integer_zero_node, NULL_TREE, NULL_TREE);
|
||
r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
|
||
gcc_assert (GET_MODE (r_save) == Pmode);
|
||
|
||
emit_move_insn (r_save, targetm.builtin_setjmp_frame_value ());
|
||
update_nonlocal_goto_save_area ();
|
||
}
|
||
|
||
/* The following was moved from init_function_start.
|
||
The move is supposed to make sdb output more accurate. */
|
||
/* Indicate the beginning of the function body,
|
||
as opposed to parm setup. */
|
||
emit_note (NOTE_INSN_FUNCTION_BEG);
|
||
|
||
gcc_assert (NOTE_P (get_last_insn ()));
|
||
|
||
parm_birth_insn = get_last_insn ();
|
||
|
||
if (crtl->profile)
|
||
{
|
||
#ifdef PROFILE_HOOK
|
||
PROFILE_HOOK (current_function_funcdef_no);
|
||
#endif
|
||
}
|
||
|
||
/* If we are doing generic stack checking, the probe should go here. */
|
||
if (flag_stack_check == GENERIC_STACK_CHECK)
|
||
stack_check_probe_note = emit_note (NOTE_INSN_DELETED);
|
||
}
|
||
|
||
/* Undo the effects of init_dummy_function_start. */
|
||
void
|
||
expand_dummy_function_end (void)
|
||
{
|
||
gcc_assert (in_dummy_function);
|
||
|
||
/* End any sequences that failed to be closed due to syntax errors. */
|
||
while (in_sequence_p ())
|
||
end_sequence ();
|
||
|
||
/* Outside function body, can't compute type's actual size
|
||
until next function's body starts. */
|
||
|
||
free_after_parsing (cfun);
|
||
free_after_compilation (cfun);
|
||
pop_cfun ();
|
||
in_dummy_function = false;
|
||
}
|
||
|
||
/* Call DOIT for each hard register used as a return value from
|
||
the current function. */
|
||
|
||
void
|
||
diddle_return_value (void (*doit) (rtx, void *), void *arg)
|
||
{
|
||
rtx outgoing = crtl->return_rtx;
|
||
|
||
if (! outgoing)
|
||
return;
|
||
|
||
if (REG_P (outgoing))
|
||
(*doit) (outgoing, arg);
|
||
else if (GET_CODE (outgoing) == PARALLEL)
|
||
{
|
||
int i;
|
||
|
||
for (i = 0; i < XVECLEN (outgoing, 0); i++)
|
||
{
|
||
rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
|
||
|
||
if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
|
||
(*doit) (x, arg);
|
||
}
|
||
}
|
||
}
|
||
|
||
static void
|
||
do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
|
||
{
|
||
emit_clobber (reg);
|
||
}
|
||
|
||
void
|
||
clobber_return_register (void)
|
||
{
|
||
diddle_return_value (do_clobber_return_reg, NULL);
|
||
|
||
/* In case we do use pseudo to return value, clobber it too. */
|
||
if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
|
||
{
|
||
tree decl_result = DECL_RESULT (current_function_decl);
|
||
rtx decl_rtl = DECL_RTL (decl_result);
|
||
if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
|
||
{
|
||
do_clobber_return_reg (decl_rtl, NULL);
|
||
}
|
||
}
|
||
}
|
||
|
||
static void
|
||
do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
|
||
{
|
||
emit_use (reg);
|
||
}
|
||
|
||
static void
|
||
use_return_register (void)
|
||
{
|
||
diddle_return_value (do_use_return_reg, NULL);
|
||
}
|
||
|
||
/* Possibly warn about unused parameters. */
|
||
void
|
||
do_warn_unused_parameter (tree fn)
|
||
{
|
||
tree decl;
|
||
|
||
for (decl = DECL_ARGUMENTS (fn);
|
||
decl; decl = DECL_CHAIN (decl))
|
||
if (!TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
|
||
&& DECL_NAME (decl) && !DECL_ARTIFICIAL (decl)
|
||
&& !TREE_NO_WARNING (decl))
|
||
warning (OPT_Wunused_parameter, "unused parameter %q+D", decl);
|
||
}
|
||
|
||
static GTY(()) rtx initial_trampoline;
|
||
|
||
/* Generate RTL for the end of the current function. */
|
||
|
||
void
|
||
expand_function_end (void)
|
||
{
|
||
rtx clobber_after;
|
||
|
||
/* If arg_pointer_save_area was referenced only from a nested
|
||
function, we will not have initialized it yet. Do that now. */
|
||
if (arg_pointer_save_area && ! crtl->arg_pointer_save_area_init)
|
||
get_arg_pointer_save_area ();
|
||
|
||
/* If we are doing generic stack checking and this function makes calls,
|
||
do a stack probe at the start of the function to ensure we have enough
|
||
space for another stack frame. */
|
||
if (flag_stack_check == GENERIC_STACK_CHECK)
|
||
{
|
||
rtx insn, seq;
|
||
|
||
for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
|
||
if (CALL_P (insn))
|
||
{
|
||
rtx max_frame_size = GEN_INT (STACK_CHECK_MAX_FRAME_SIZE);
|
||
start_sequence ();
|
||
if (STACK_CHECK_MOVING_SP)
|
||
anti_adjust_stack_and_probe (max_frame_size, true);
|
||
else
|
||
probe_stack_range (STACK_OLD_CHECK_PROTECT, max_frame_size);
|
||
seq = get_insns ();
|
||
end_sequence ();
|
||
set_insn_locators (seq, prologue_locator);
|
||
emit_insn_before (seq, stack_check_probe_note);
|
||
break;
|
||
}
|
||
}
|
||
|
||
/* End any sequences that failed to be closed due to syntax errors. */
|
||
while (in_sequence_p ())
|
||
end_sequence ();
|
||
|
||
clear_pending_stack_adjust ();
|
||
do_pending_stack_adjust ();
|
||
|
||
/* Output a linenumber for the end of the function.
|
||
SDB depends on this. */
|
||
set_curr_insn_source_location (input_location);
|
||
|
||
/* Before the return label (if any), clobber the return
|
||
registers so that they are not propagated live to the rest of
|
||
the function. This can only happen with functions that drop
|
||
through; if there had been a return statement, there would
|
||
have either been a return rtx, or a jump to the return label.
|
||
|
||
We delay actual code generation after the current_function_value_rtx
|
||
is computed. */
|
||
clobber_after = get_last_insn ();
|
||
|
||
/* Output the label for the actual return from the function. */
|
||
emit_label (return_label);
|
||
|
||
if (targetm_common.except_unwind_info (&global_options) == UI_SJLJ)
|
||
{
|
||
/* Let except.c know where it should emit the call to unregister
|
||
the function context for sjlj exceptions. */
|
||
if (flag_exceptions)
|
||
sjlj_emit_function_exit_after (get_last_insn ());
|
||
}
|
||
else
|
||
{
|
||
/* We want to ensure that instructions that may trap are not
|
||
moved into the epilogue by scheduling, because we don't
|
||
always emit unwind information for the epilogue. */
|
||
if (cfun->can_throw_non_call_exceptions)
|
||
emit_insn (gen_blockage ());
|
||
}
|
||
|
||
/* If this is an implementation of throw, do what's necessary to
|
||
communicate between __builtin_eh_return and the epilogue. */
|
||
expand_eh_return ();
|
||
|
||
/* If scalar return value was computed in a pseudo-reg, or was a named
|
||
return value that got dumped to the stack, copy that to the hard
|
||
return register. */
|
||
if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
|
||
{
|
||
tree decl_result = DECL_RESULT (current_function_decl);
|
||
rtx decl_rtl = DECL_RTL (decl_result);
|
||
|
||
if (REG_P (decl_rtl)
|
||
? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
|
||
: DECL_REGISTER (decl_result))
|
||
{
|
||
rtx real_decl_rtl = crtl->return_rtx;
|
||
|
||
/* This should be set in assign_parms. */
|
||
gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl));
|
||
|
||
/* If this is a BLKmode structure being returned in registers,
|
||
then use the mode computed in expand_return. Note that if
|
||
decl_rtl is memory, then its mode may have been changed,
|
||
but that crtl->return_rtx has not. */
|
||
if (GET_MODE (real_decl_rtl) == BLKmode)
|
||
PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
|
||
|
||
/* If a non-BLKmode return value should be padded at the least
|
||
significant end of the register, shift it left by the appropriate
|
||
amount. BLKmode results are handled using the group load/store
|
||
machinery. */
|
||
if (TYPE_MODE (TREE_TYPE (decl_result)) != BLKmode
|
||
&& targetm.calls.return_in_msb (TREE_TYPE (decl_result)))
|
||
{
|
||
emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl),
|
||
REGNO (real_decl_rtl)),
|
||
decl_rtl);
|
||
shift_return_value (GET_MODE (decl_rtl), true, real_decl_rtl);
|
||
}
|
||
/* If a named return value dumped decl_return to memory, then
|
||
we may need to re-do the PROMOTE_MODE signed/unsigned
|
||
extension. */
|
||
else if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
|
||
{
|
||
int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result));
|
||
promote_function_mode (TREE_TYPE (decl_result),
|
||
GET_MODE (decl_rtl), &unsignedp,
|
||
TREE_TYPE (current_function_decl), 1);
|
||
|
||
convert_move (real_decl_rtl, decl_rtl, unsignedp);
|
||
}
|
||
else if (GET_CODE (real_decl_rtl) == PARALLEL)
|
||
{
|
||
/* If expand_function_start has created a PARALLEL for decl_rtl,
|
||
move the result to the real return registers. Otherwise, do
|
||
a group load from decl_rtl for a named return. */
|
||
if (GET_CODE (decl_rtl) == PARALLEL)
|
||
emit_group_move (real_decl_rtl, decl_rtl);
|
||
else
|
||
emit_group_load (real_decl_rtl, decl_rtl,
|
||
TREE_TYPE (decl_result),
|
||
int_size_in_bytes (TREE_TYPE (decl_result)));
|
||
}
|
||
/* In the case of complex integer modes smaller than a word, we'll
|
||
need to generate some non-trivial bitfield insertions. Do that
|
||
on a pseudo and not the hard register. */
|
||
else if (GET_CODE (decl_rtl) == CONCAT
|
||
&& GET_MODE_CLASS (GET_MODE (decl_rtl)) == MODE_COMPLEX_INT
|
||
&& GET_MODE_BITSIZE (GET_MODE (decl_rtl)) <= BITS_PER_WORD)
|
||
{
|
||
int old_generating_concat_p;
|
||
rtx tmp;
|
||
|
||
old_generating_concat_p = generating_concat_p;
|
||
generating_concat_p = 0;
|
||
tmp = gen_reg_rtx (GET_MODE (decl_rtl));
|
||
generating_concat_p = old_generating_concat_p;
|
||
|
||
emit_move_insn (tmp, decl_rtl);
|
||
emit_move_insn (real_decl_rtl, tmp);
|
||
}
|
||
else
|
||
emit_move_insn (real_decl_rtl, decl_rtl);
|
||
}
|
||
}
|
||
|
||
/* If returning a structure, arrange to return the address of the value
|
||
in a place where debuggers expect to find it.
|
||
|
||
If returning a structure PCC style,
|
||
the caller also depends on this value.
|
||
And cfun->returns_pcc_struct is not necessarily set. */
|
||
if (cfun->returns_struct
|
||
|| cfun->returns_pcc_struct)
|
||
{
|
||
rtx value_address = DECL_RTL (DECL_RESULT (current_function_decl));
|
||
tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
|
||
rtx outgoing;
|
||
|
||
if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
|
||
type = TREE_TYPE (type);
|
||
else
|
||
value_address = XEXP (value_address, 0);
|
||
|
||
outgoing = targetm.calls.function_value (build_pointer_type (type),
|
||
current_function_decl, true);
|
||
|
||
/* Mark this as a function return value so integrate will delete the
|
||
assignment and USE below when inlining this function. */
|
||
REG_FUNCTION_VALUE_P (outgoing) = 1;
|
||
|
||
/* The address may be ptr_mode and OUTGOING may be Pmode. */
|
||
value_address = convert_memory_address (GET_MODE (outgoing),
|
||
value_address);
|
||
|
||
emit_move_insn (outgoing, value_address);
|
||
|
||
/* Show return register used to hold result (in this case the address
|
||
of the result. */
|
||
crtl->return_rtx = outgoing;
|
||
}
|
||
|
||
/* Emit the actual code to clobber return register. */
|
||
{
|
||
rtx seq;
|
||
|
||
start_sequence ();
|
||
clobber_return_register ();
|
||
seq = get_insns ();
|
||
end_sequence ();
|
||
|
||
emit_insn_after (seq, clobber_after);
|
||
}
|
||
|
||
/* Output the label for the naked return from the function. */
|
||
if (naked_return_label)
|
||
emit_label (naked_return_label);
|
||
|
||
/* @@@ This is a kludge. We want to ensure that instructions that
|
||
may trap are not moved into the epilogue by scheduling, because
|
||
we don't always emit unwind information for the epilogue. */
|
||
if (cfun->can_throw_non_call_exceptions
|
||
&& targetm_common.except_unwind_info (&global_options) != UI_SJLJ)
|
||
emit_insn (gen_blockage ());
|
||
|
||
/* If stack protection is enabled for this function, check the guard. */
|
||
if (crtl->stack_protect_guard)
|
||
stack_protect_epilogue ();
|
||
|
||
/* If we had calls to alloca, and this machine needs
|
||
an accurate stack pointer to exit the function,
|
||
insert some code to save and restore the stack pointer. */
|
||
if (! EXIT_IGNORE_STACK
|
||
&& cfun->calls_alloca)
|
||
{
|
||
rtx tem = 0, seq;
|
||
|
||
start_sequence ();
|
||
emit_stack_save (SAVE_FUNCTION, &tem);
|
||
seq = get_insns ();
|
||
end_sequence ();
|
||
emit_insn_before (seq, parm_birth_insn);
|
||
|
||
emit_stack_restore (SAVE_FUNCTION, tem);
|
||
}
|
||
|
||
/* ??? This should no longer be necessary since stupid is no longer with
|
||
us, but there are some parts of the compiler (eg reload_combine, and
|
||
sh mach_dep_reorg) that still try and compute their own lifetime info
|
||
instead of using the general framework. */
|
||
use_return_register ();
|
||
}
|
||
|
||
rtx
|
||
get_arg_pointer_save_area (void)
|
||
{
|
||
rtx ret = arg_pointer_save_area;
|
||
|
||
if (! ret)
|
||
{
|
||
ret = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
|
||
arg_pointer_save_area = ret;
|
||
}
|
||
|
||
if (! crtl->arg_pointer_save_area_init)
|
||
{
|
||
rtx seq;
|
||
|
||
/* Save the arg pointer at the beginning of the function. The
|
||
generated stack slot may not be a valid memory address, so we
|
||
have to check it and fix it if necessary. */
|
||
start_sequence ();
|
||
emit_move_insn (validize_mem (ret),
|
||
crtl->args.internal_arg_pointer);
|
||
seq = get_insns ();
|
||
end_sequence ();
|
||
|
||
push_topmost_sequence ();
|
||
emit_insn_after (seq, entry_of_function ());
|
||
pop_topmost_sequence ();
|
||
|
||
crtl->arg_pointer_save_area_init = true;
|
||
}
|
||
|
||
return ret;
|
||
}
|
||
|
||
/* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
|
||
for the first time. */
|
||
|
||
static void
|
||
record_insns (rtx insns, rtx end, htab_t *hashp)
|
||
{
|
||
rtx tmp;
|
||
htab_t hash = *hashp;
|
||
|
||
if (hash == NULL)
|
||
*hashp = hash
|
||
= htab_create_ggc (17, htab_hash_pointer, htab_eq_pointer, NULL);
|
||
|
||
for (tmp = insns; tmp != end; tmp = NEXT_INSN (tmp))
|
||
{
|
||
void **slot = htab_find_slot (hash, tmp, INSERT);
|
||
gcc_assert (*slot == NULL);
|
||
*slot = tmp;
|
||
}
|
||
}
|
||
|
||
/* INSN has been duplicated or replaced by as COPY, perhaps by duplicating a
|
||
basic block, splitting or peepholes. If INSN is a prologue or epilogue
|
||
insn, then record COPY as well. */
|
||
|
||
void
|
||
maybe_copy_prologue_epilogue_insn (rtx insn, rtx copy)
|
||
{
|
||
htab_t hash;
|
||
void **slot;
|
||
|
||
hash = epilogue_insn_hash;
|
||
if (!hash || !htab_find (hash, insn))
|
||
{
|
||
hash = prologue_insn_hash;
|
||
if (!hash || !htab_find (hash, insn))
|
||
return;
|
||
}
|
||
|
||
slot = htab_find_slot (hash, copy, INSERT);
|
||
gcc_assert (*slot == NULL);
|
||
*slot = copy;
|
||
}
|
||
|
||
/* Set the locator of the insn chain starting at INSN to LOC. */
|
||
static void
|
||
set_insn_locators (rtx insn, int loc)
|
||
{
|
||
while (insn != NULL_RTX)
|
||
{
|
||
if (INSN_P (insn))
|
||
INSN_LOCATOR (insn) = loc;
|
||
insn = NEXT_INSN (insn);
|
||
}
|
||
}
|
||
|
||
/* Determine if any INSNs in HASH are, or are part of, INSN. Because
|
||
we can be running after reorg, SEQUENCE rtl is possible. */
|
||
|
||
static bool
|
||
contains (const_rtx insn, htab_t hash)
|
||
{
|
||
if (hash == NULL)
|
||
return false;
|
||
|
||
if (NONJUMP_INSN_P (insn) && GET_CODE (PATTERN (insn)) == SEQUENCE)
|
||
{
|
||
int i;
|
||
for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
|
||
if (htab_find (hash, XVECEXP (PATTERN (insn), 0, i)))
|
||
return true;
|
||
return false;
|
||
}
|
||
|
||
return htab_find (hash, insn) != NULL;
|
||
}
|
||
|
||
int
|
||
prologue_epilogue_contains (const_rtx insn)
|
||
{
|
||
if (contains (insn, prologue_insn_hash))
|
||
return 1;
|
||
if (contains (insn, epilogue_insn_hash))
|
||
return 1;
|
||
return 0;
|
||
}
|
||
|
||
#ifdef HAVE_simple_return
|
||
|
||
/* Return true if INSN requires the stack frame to be set up.
|
||
PROLOGUE_USED contains the hard registers used in the function
|
||
prologue. SET_UP_BY_PROLOGUE is the set of registers we expect the
|
||
prologue to set up for the function. */
|
||
bool
|
||
requires_stack_frame_p (rtx insn, HARD_REG_SET prologue_used,
|
||
HARD_REG_SET set_up_by_prologue)
|
||
{
|
||
df_ref *df_rec;
|
||
HARD_REG_SET hardregs;
|
||
unsigned regno;
|
||
|
||
if (CALL_P (insn))
|
||
return !SIBLING_CALL_P (insn);
|
||
|
||
/* We need a frame to get the unique CFA expected by the unwinder. */
|
||
if (cfun->can_throw_non_call_exceptions && can_throw_internal (insn))
|
||
return true;
|
||
|
||
CLEAR_HARD_REG_SET (hardregs);
|
||
for (df_rec = DF_INSN_DEFS (insn); *df_rec; df_rec++)
|
||
{
|
||
rtx dreg = DF_REF_REG (*df_rec);
|
||
|
||
if (!REG_P (dreg))
|
||
continue;
|
||
|
||
add_to_hard_reg_set (&hardregs, GET_MODE (dreg),
|
||
REGNO (dreg));
|
||
}
|
||
if (hard_reg_set_intersect_p (hardregs, prologue_used))
|
||
return true;
|
||
AND_COMPL_HARD_REG_SET (hardregs, call_used_reg_set);
|
||
for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
|
||
if (TEST_HARD_REG_BIT (hardregs, regno)
|
||
&& df_regs_ever_live_p (regno))
|
||
return true;
|
||
|
||
for (df_rec = DF_INSN_USES (insn); *df_rec; df_rec++)
|
||
{
|
||
rtx reg = DF_REF_REG (*df_rec);
|
||
|
||
if (!REG_P (reg))
|
||
continue;
|
||
|
||
add_to_hard_reg_set (&hardregs, GET_MODE (reg),
|
||
REGNO (reg));
|
||
}
|
||
if (hard_reg_set_intersect_p (hardregs, set_up_by_prologue))
|
||
return true;
|
||
|
||
return false;
|
||
}
|
||
|
||
/* See whether BB has a single successor that uses [REGNO, END_REGNO),
|
||
and if BB is its only predecessor. Return that block if so,
|
||
otherwise return null. */
|
||
|
||
static basic_block
|
||
next_block_for_reg (basic_block bb, int regno, int end_regno)
|
||
{
|
||
edge e, live_edge;
|
||
edge_iterator ei;
|
||
bitmap live;
|
||
int i;
|
||
|
||
live_edge = NULL;
|
||
FOR_EACH_EDGE (e, ei, bb->succs)
|
||
{
|
||
live = df_get_live_in (e->dest);
|
||
for (i = regno; i < end_regno; i++)
|
||
if (REGNO_REG_SET_P (live, i))
|
||
{
|
||
if (live_edge && live_edge != e)
|
||
return NULL;
|
||
live_edge = e;
|
||
}
|
||
}
|
||
|
||
/* We can sometimes encounter dead code. Don't try to move it
|
||
into the exit block. */
|
||
if (!live_edge || live_edge->dest == EXIT_BLOCK_PTR)
|
||
return NULL;
|
||
|
||
/* Reject targets of abnormal edges. This is needed for correctness
|
||
on ports like Alpha and MIPS, whose pic_offset_table_rtx can die on
|
||
exception edges even though it is generally treated as call-saved
|
||
for the majority of the compilation. Moving across abnormal edges
|
||
isn't going to be interesting for shrink-wrap usage anyway. */
|
||
if (live_edge->flags & EDGE_ABNORMAL)
|
||
return NULL;
|
||
|
||
if (EDGE_COUNT (live_edge->dest->preds) > 1)
|
||
return NULL;
|
||
|
||
return live_edge->dest;
|
||
}
|
||
|
||
/* Try to move INSN from BB to a successor. Return true on success.
|
||
USES and DEFS are the set of registers that are used and defined
|
||
after INSN in BB. */
|
||
|
||
static bool
|
||
move_insn_for_shrink_wrap (basic_block bb, rtx insn,
|
||
const HARD_REG_SET uses,
|
||
const HARD_REG_SET defs)
|
||
{
|
||
rtx set, src, dest;
|
||
bitmap live_out, live_in, bb_uses, bb_defs;
|
||
unsigned int i, dregno, end_dregno, sregno, end_sregno;
|
||
basic_block next_block;
|
||
|
||
/* Look for a simple register copy. */
|
||
set = single_set (insn);
|
||
if (!set)
|
||
return false;
|
||
src = SET_SRC (set);
|
||
dest = SET_DEST (set);
|
||
if (!REG_P (dest) || !REG_P (src))
|
||
return false;
|
||
|
||
/* Make sure that the source register isn't defined later in BB. */
|
||
sregno = REGNO (src);
|
||
end_sregno = END_REGNO (src);
|
||
if (overlaps_hard_reg_set_p (defs, GET_MODE (src), sregno))
|
||
return false;
|
||
|
||
/* Make sure that the destination register isn't referenced later in BB. */
|
||
dregno = REGNO (dest);
|
||
end_dregno = END_REGNO (dest);
|
||
if (overlaps_hard_reg_set_p (uses, GET_MODE (dest), dregno)
|
||
|| overlaps_hard_reg_set_p (defs, GET_MODE (dest), dregno))
|
||
return false;
|
||
|
||
/* See whether there is a successor block to which we could move INSN. */
|
||
next_block = next_block_for_reg (bb, dregno, end_dregno);
|
||
if (!next_block)
|
||
return false;
|
||
|
||
/* At this point we are committed to moving INSN, but let's try to
|
||
move it as far as we can. */
|
||
do
|
||
{
|
||
live_out = df_get_live_out (bb);
|
||
live_in = df_get_live_in (next_block);
|
||
bb = next_block;
|
||
|
||
/* Check whether BB uses DEST or clobbers DEST. We need to add
|
||
INSN to BB if so. Either way, DEST is no longer live on entry,
|
||
except for any part that overlaps SRC (next loop). */
|
||
bb_uses = &DF_LR_BB_INFO (bb)->use;
|
||
bb_defs = &DF_LR_BB_INFO (bb)->def;
|
||
for (i = dregno; i < end_dregno; i++)
|
||
{
|
||
if (REGNO_REG_SET_P (bb_uses, i) || REGNO_REG_SET_P (bb_defs, i))
|
||
next_block = NULL;
|
||
CLEAR_REGNO_REG_SET (live_out, i);
|
||
CLEAR_REGNO_REG_SET (live_in, i);
|
||
}
|
||
|
||
/* Check whether BB clobbers SRC. We need to add INSN to BB if so.
|
||
Either way, SRC is now live on entry. */
|
||
for (i = sregno; i < end_sregno; i++)
|
||
{
|
||
if (REGNO_REG_SET_P (bb_defs, i))
|
||
next_block = NULL;
|
||
SET_REGNO_REG_SET (live_out, i);
|
||
SET_REGNO_REG_SET (live_in, i);
|
||
}
|
||
|
||
/* If we don't need to add the move to BB, look for a single
|
||
successor block. */
|
||
if (next_block)
|
||
next_block = next_block_for_reg (next_block, dregno, end_dregno);
|
||
}
|
||
while (next_block);
|
||
|
||
/* BB now defines DEST. It only uses the parts of DEST that overlap SRC
|
||
(next loop). */
|
||
for (i = dregno; i < end_dregno; i++)
|
||
{
|
||
CLEAR_REGNO_REG_SET (bb_uses, i);
|
||
SET_REGNO_REG_SET (bb_defs, i);
|
||
}
|
||
|
||
/* BB now uses SRC. */
|
||
for (i = sregno; i < end_sregno; i++)
|
||
SET_REGNO_REG_SET (bb_uses, i);
|
||
|
||
emit_insn_after (PATTERN (insn), bb_note (bb));
|
||
delete_insn (insn);
|
||
return true;
|
||
}
|
||
|
||
/* Look for register copies in the first block of the function, and move
|
||
them down into successor blocks if the register is used only on one
|
||
path. This exposes more opportunities for shrink-wrapping. These
|
||
kinds of sets often occur when incoming argument registers are moved
|
||
to call-saved registers because their values are live across one or
|
||
more calls during the function. */
|
||
|
||
static void
|
||
prepare_shrink_wrap (basic_block entry_block)
|
||
{
|
||
rtx insn, curr, x;
|
||
HARD_REG_SET uses, defs;
|
||
df_ref *ref;
|
||
|
||
CLEAR_HARD_REG_SET (uses);
|
||
CLEAR_HARD_REG_SET (defs);
|
||
FOR_BB_INSNS_REVERSE_SAFE (entry_block, insn, curr)
|
||
if (NONDEBUG_INSN_P (insn)
|
||
&& !move_insn_for_shrink_wrap (entry_block, insn, uses, defs))
|
||
{
|
||
/* Add all defined registers to DEFs. */
|
||
for (ref = DF_INSN_DEFS (insn); *ref; ref++)
|
||
{
|
||
x = DF_REF_REG (*ref);
|
||
if (REG_P (x) && HARD_REGISTER_P (x))
|
||
SET_HARD_REG_BIT (defs, REGNO (x));
|
||
}
|
||
|
||
/* Add all used registers to USESs. */
|
||
for (ref = DF_INSN_USES (insn); *ref; ref++)
|
||
{
|
||
x = DF_REF_REG (*ref);
|
||
if (REG_P (x) && HARD_REGISTER_P (x))
|
||
SET_HARD_REG_BIT (uses, REGNO (x));
|
||
}
|
||
}
|
||
}
|
||
|
||
#endif
|
||
|
||
#ifdef HAVE_return
|
||
/* Insert use of return register before the end of BB. */
|
||
|
||
static void
|
||
emit_use_return_register_into_block (basic_block bb)
|
||
{
|
||
rtx seq;
|
||
start_sequence ();
|
||
use_return_register ();
|
||
seq = get_insns ();
|
||
end_sequence ();
|
||
emit_insn_before (seq, BB_END (bb));
|
||
}
|
||
|
||
|
||
/* Create a return pattern, either simple_return or return, depending on
|
||
simple_p. */
|
||
|
||
static rtx
|
||
gen_return_pattern (bool simple_p)
|
||
{
|
||
#ifdef HAVE_simple_return
|
||
return simple_p ? gen_simple_return () : gen_return ();
|
||
#else
|
||
gcc_assert (!simple_p);
|
||
return gen_return ();
|
||
#endif
|
||
}
|
||
|
||
/* Insert an appropriate return pattern at the end of block BB. This
|
||
also means updating block_for_insn appropriately. SIMPLE_P is
|
||
the same as in gen_return_pattern and passed to it. */
|
||
|
||
static void
|
||
emit_return_into_block (bool simple_p, basic_block bb)
|
||
{
|
||
rtx jump, pat;
|
||
jump = emit_jump_insn_after (gen_return_pattern (simple_p), BB_END (bb));
|
||
pat = PATTERN (jump);
|
||
if (GET_CODE (pat) == PARALLEL)
|
||
pat = XVECEXP (pat, 0, 0);
|
||
gcc_assert (ANY_RETURN_P (pat));
|
||
JUMP_LABEL (jump) = pat;
|
||
}
|
||
#endif
|
||
|
||
/* Set JUMP_LABEL for a return insn. */
|
||
|
||
void
|
||
set_return_jump_label (rtx returnjump)
|
||
{
|
||
rtx pat = PATTERN (returnjump);
|
||
if (GET_CODE (pat) == PARALLEL)
|
||
pat = XVECEXP (pat, 0, 0);
|
||
if (ANY_RETURN_P (pat))
|
||
JUMP_LABEL (returnjump) = pat;
|
||
else
|
||
JUMP_LABEL (returnjump) = ret_rtx;
|
||
}
|
||
|
||
#ifdef HAVE_simple_return
|
||
/* Create a copy of BB instructions and insert at BEFORE. Redirect
|
||
preds of BB to COPY_BB if they don't appear in NEED_PROLOGUE. */
|
||
static void
|
||
dup_block_and_redirect (basic_block bb, basic_block copy_bb, rtx before,
|
||
bitmap_head *need_prologue)
|
||
{
|
||
edge_iterator ei;
|
||
edge e;
|
||
rtx insn = BB_END (bb);
|
||
|
||
/* We know BB has a single successor, so there is no need to copy a
|
||
simple jump at the end of BB. */
|
||
if (simplejump_p (insn))
|
||
insn = PREV_INSN (insn);
|
||
|
||
start_sequence ();
|
||
duplicate_insn_chain (BB_HEAD (bb), insn);
|
||
if (dump_file)
|
||
{
|
||
unsigned count = 0;
|
||
for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
|
||
if (active_insn_p (insn))
|
||
++count;
|
||
fprintf (dump_file, "Duplicating bb %d to bb %d, %u active insns.\n",
|
||
bb->index, copy_bb->index, count);
|
||
}
|
||
insn = get_insns ();
|
||
end_sequence ();
|
||
emit_insn_before (insn, before);
|
||
|
||
/* Redirect all the paths that need no prologue into copy_bb. */
|
||
for (ei = ei_start (bb->preds); (e = ei_safe_edge (ei)); )
|
||
if (!bitmap_bit_p (need_prologue, e->src->index))
|
||
{
|
||
redirect_edge_and_branch_force (e, copy_bb);
|
||
continue;
|
||
}
|
||
else
|
||
ei_next (&ei);
|
||
}
|
||
#endif
|
||
|
||
#if defined (HAVE_return) || defined (HAVE_simple_return)
|
||
/* Return true if there are any active insns between HEAD and TAIL. */
|
||
static bool
|
||
active_insn_between (rtx head, rtx tail)
|
||
{
|
||
while (tail)
|
||
{
|
||
if (active_insn_p (tail))
|
||
return true;
|
||
if (tail == head)
|
||
return false;
|
||
tail = PREV_INSN (tail);
|
||
}
|
||
return false;
|
||
}
|
||
|
||
/* LAST_BB is a block that exits, and empty of active instructions.
|
||
Examine its predecessors for jumps that can be converted to
|
||
(conditional) returns. */
|
||
static VEC (edge, heap) *
|
||
convert_jumps_to_returns (basic_block last_bb, bool simple_p,
|
||
VEC (edge, heap) *unconverted ATTRIBUTE_UNUSED)
|
||
{
|
||
int i;
|
||
basic_block bb;
|
||
rtx label;
|
||
edge_iterator ei;
|
||
edge e;
|
||
VEC(basic_block,heap) *src_bbs;
|
||
|
||
src_bbs = VEC_alloc (basic_block, heap, EDGE_COUNT (last_bb->preds));
|
||
FOR_EACH_EDGE (e, ei, last_bb->preds)
|
||
if (e->src != ENTRY_BLOCK_PTR)
|
||
VEC_quick_push (basic_block, src_bbs, e->src);
|
||
|
||
label = BB_HEAD (last_bb);
|
||
|
||
FOR_EACH_VEC_ELT (basic_block, src_bbs, i, bb)
|
||
{
|
||
rtx jump = BB_END (bb);
|
||
|
||
if (!JUMP_P (jump) || JUMP_LABEL (jump) != label)
|
||
continue;
|
||
|
||
e = find_edge (bb, last_bb);
|
||
|
||
/* If we have an unconditional jump, we can replace that
|
||
with a simple return instruction. */
|
||
if (simplejump_p (jump))
|
||
{
|
||
/* The use of the return register might be present in the exit
|
||
fallthru block. Either:
|
||
- removing the use is safe, and we should remove the use in
|
||
the exit fallthru block, or
|
||
- removing the use is not safe, and we should add it here.
|
||
For now, we conservatively choose the latter. Either of the
|
||
2 helps in crossjumping. */
|
||
emit_use_return_register_into_block (bb);
|
||
|
||
emit_return_into_block (simple_p, bb);
|
||
delete_insn (jump);
|
||
}
|
||
|
||
/* If we have a conditional jump branching to the last
|
||
block, we can try to replace that with a conditional
|
||
return instruction. */
|
||
else if (condjump_p (jump))
|
||
{
|
||
rtx dest;
|
||
|
||
if (simple_p)
|
||
dest = simple_return_rtx;
|
||
else
|
||
dest = ret_rtx;
|
||
if (!redirect_jump (jump, dest, 0))
|
||
{
|
||
#ifdef HAVE_simple_return
|
||
if (simple_p)
|
||
{
|
||
if (dump_file)
|
||
fprintf (dump_file,
|
||
"Failed to redirect bb %d branch.\n", bb->index);
|
||
VEC_safe_push (edge, heap, unconverted, e);
|
||
}
|
||
#endif
|
||
continue;
|
||
}
|
||
|
||
/* See comment in simplejump_p case above. */
|
||
emit_use_return_register_into_block (bb);
|
||
|
||
/* If this block has only one successor, it both jumps
|
||
and falls through to the fallthru block, so we can't
|
||
delete the edge. */
|
||
if (single_succ_p (bb))
|
||
continue;
|
||
}
|
||
else
|
||
{
|
||
#ifdef HAVE_simple_return
|
||
if (simple_p)
|
||
{
|
||
if (dump_file)
|
||
fprintf (dump_file,
|
||
"Failed to redirect bb %d branch.\n", bb->index);
|
||
VEC_safe_push (edge, heap, unconverted, e);
|
||
}
|
||
#endif
|
||
continue;
|
||
}
|
||
|
||
/* Fix up the CFG for the successful change we just made. */
|
||
redirect_edge_succ (e, EXIT_BLOCK_PTR);
|
||
e->flags &= ~EDGE_CROSSING;
|
||
}
|
||
VEC_free (basic_block, heap, src_bbs);
|
||
return unconverted;
|
||
}
|
||
|
||
/* Emit a return insn for the exit fallthru block. */
|
||
static basic_block
|
||
emit_return_for_exit (edge exit_fallthru_edge, bool simple_p)
|
||
{
|
||
basic_block last_bb = exit_fallthru_edge->src;
|
||
|
||
if (JUMP_P (BB_END (last_bb)))
|
||
{
|
||
last_bb = split_edge (exit_fallthru_edge);
|
||
exit_fallthru_edge = single_succ_edge (last_bb);
|
||
}
|
||
emit_barrier_after (BB_END (last_bb));
|
||
emit_return_into_block (simple_p, last_bb);
|
||
exit_fallthru_edge->flags &= ~EDGE_FALLTHRU;
|
||
return last_bb;
|
||
}
|
||
#endif
|
||
|
||
|
||
/* Generate the prologue and epilogue RTL if the machine supports it. Thread
|
||
this into place with notes indicating where the prologue ends and where
|
||
the epilogue begins. Update the basic block information when possible.
|
||
|
||
Notes on epilogue placement:
|
||
There are several kinds of edges to the exit block:
|
||
* a single fallthru edge from LAST_BB
|
||
* possibly, edges from blocks containing sibcalls
|
||
* possibly, fake edges from infinite loops
|
||
|
||
The epilogue is always emitted on the fallthru edge from the last basic
|
||
block in the function, LAST_BB, into the exit block.
|
||
|
||
If LAST_BB is empty except for a label, it is the target of every
|
||
other basic block in the function that ends in a return. If a
|
||
target has a return or simple_return pattern (possibly with
|
||
conditional variants), these basic blocks can be changed so that a
|
||
return insn is emitted into them, and their target is adjusted to
|
||
the real exit block.
|
||
|
||
Notes on shrink wrapping: We implement a fairly conservative
|
||
version of shrink-wrapping rather than the textbook one. We only
|
||
generate a single prologue and a single epilogue. This is
|
||
sufficient to catch a number of interesting cases involving early
|
||
exits.
|
||
|
||
First, we identify the blocks that require the prologue to occur before
|
||
them. These are the ones that modify a call-saved register, or reference
|
||
any of the stack or frame pointer registers. To simplify things, we then
|
||
mark everything reachable from these blocks as also requiring a prologue.
|
||
This takes care of loops automatically, and avoids the need to examine
|
||
whether MEMs reference the frame, since it is sufficient to check for
|
||
occurrences of the stack or frame pointer.
|
||
|
||
We then compute the set of blocks for which the need for a prologue
|
||
is anticipatable (borrowing terminology from the shrink-wrapping
|
||
description in Muchnick's book). These are the blocks which either
|
||
require a prologue themselves, or those that have only successors
|
||
where the prologue is anticipatable. The prologue needs to be
|
||
inserted on all edges from BB1->BB2 where BB2 is in ANTIC and BB1
|
||
is not. For the moment, we ensure that only one such edge exists.
|
||
|
||
The epilogue is placed as described above, but we make a
|
||
distinction between inserting return and simple_return patterns
|
||
when modifying other blocks that end in a return. Blocks that end
|
||
in a sibcall omit the sibcall_epilogue if the block is not in
|
||
ANTIC. */
|
||
|
||
static void
|
||
thread_prologue_and_epilogue_insns (void)
|
||
{
|
||
bool inserted;
|
||
#ifdef HAVE_simple_return
|
||
VEC (edge, heap) *unconverted_simple_returns = NULL;
|
||
bool nonempty_prologue;
|
||
bitmap_head bb_flags;
|
||
unsigned max_grow_size;
|
||
#endif
|
||
rtx returnjump;
|
||
rtx seq ATTRIBUTE_UNUSED, epilogue_end ATTRIBUTE_UNUSED;
|
||
rtx prologue_seq ATTRIBUTE_UNUSED, split_prologue_seq ATTRIBUTE_UNUSED;
|
||
edge e, entry_edge, orig_entry_edge, exit_fallthru_edge;
|
||
edge_iterator ei;
|
||
|
||
df_analyze ();
|
||
|
||
rtl_profile_for_bb (ENTRY_BLOCK_PTR);
|
||
|
||
inserted = false;
|
||
seq = NULL_RTX;
|
||
epilogue_end = NULL_RTX;
|
||
returnjump = NULL_RTX;
|
||
|
||
/* Can't deal with multiple successors of the entry block at the
|
||
moment. Function should always have at least one entry
|
||
point. */
|
||
gcc_assert (single_succ_p (ENTRY_BLOCK_PTR));
|
||
entry_edge = single_succ_edge (ENTRY_BLOCK_PTR);
|
||
orig_entry_edge = entry_edge;
|
||
|
||
split_prologue_seq = NULL_RTX;
|
||
if (flag_split_stack
|
||
&& (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (cfun->decl))
|
||
== NULL))
|
||
{
|
||
#ifndef HAVE_split_stack_prologue
|
||
gcc_unreachable ();
|
||
#else
|
||
gcc_assert (HAVE_split_stack_prologue);
|
||
|
||
start_sequence ();
|
||
emit_insn (gen_split_stack_prologue ());
|
||
split_prologue_seq = get_insns ();
|
||
end_sequence ();
|
||
|
||
record_insns (split_prologue_seq, NULL, &prologue_insn_hash);
|
||
set_insn_locators (split_prologue_seq, prologue_locator);
|
||
#endif
|
||
}
|
||
|
||
prologue_seq = NULL_RTX;
|
||
#ifdef HAVE_prologue
|
||
if (HAVE_prologue)
|
||
{
|
||
start_sequence ();
|
||
seq = gen_prologue ();
|
||
emit_insn (seq);
|
||
|
||
/* Insert an explicit USE for the frame pointer
|
||
if the profiling is on and the frame pointer is required. */
|
||
if (crtl->profile && frame_pointer_needed)
|
||
emit_use (hard_frame_pointer_rtx);
|
||
|
||
/* Retain a map of the prologue insns. */
|
||
record_insns (seq, NULL, &prologue_insn_hash);
|
||
emit_note (NOTE_INSN_PROLOGUE_END);
|
||
|
||
/* Ensure that instructions are not moved into the prologue when
|
||
profiling is on. The call to the profiling routine can be
|
||
emitted within the live range of a call-clobbered register. */
|
||
if (!targetm.profile_before_prologue () && crtl->profile)
|
||
emit_insn (gen_blockage ());
|
||
|
||
prologue_seq = get_insns ();
|
||
end_sequence ();
|
||
set_insn_locators (prologue_seq, prologue_locator);
|
||
}
|
||
#endif
|
||
|
||
#ifdef HAVE_simple_return
|
||
bitmap_initialize (&bb_flags, &bitmap_default_obstack);
|
||
|
||
/* Try to perform a kind of shrink-wrapping, making sure the
|
||
prologue/epilogue is emitted only around those parts of the
|
||
function that require it. */
|
||
|
||
nonempty_prologue = false;
|
||
for (seq = prologue_seq; seq; seq = NEXT_INSN (seq))
|
||
if (!NOTE_P (seq) || NOTE_KIND (seq) != NOTE_INSN_PROLOGUE_END)
|
||
{
|
||
nonempty_prologue = true;
|
||
break;
|
||
}
|
||
|
||
if (flag_shrink_wrap && HAVE_simple_return
|
||
&& (targetm.profile_before_prologue () || !crtl->profile)
|
||
&& nonempty_prologue && !crtl->calls_eh_return)
|
||
{
|
||
HARD_REG_SET prologue_clobbered, prologue_used, live_on_edge;
|
||
struct hard_reg_set_container set_up_by_prologue;
|
||
rtx p_insn;
|
||
VEC(basic_block, heap) *vec;
|
||
basic_block bb;
|
||
bitmap_head bb_antic_flags;
|
||
bitmap_head bb_on_list;
|
||
bitmap_head bb_tail;
|
||
|
||
if (dump_file)
|
||
fprintf (dump_file, "Attempting shrink-wrapping optimization.\n");
|
||
|
||
/* Compute the registers set and used in the prologue. */
|
||
CLEAR_HARD_REG_SET (prologue_clobbered);
|
||
CLEAR_HARD_REG_SET (prologue_used);
|
||
for (p_insn = prologue_seq; p_insn; p_insn = NEXT_INSN (p_insn))
|
||
{
|
||
HARD_REG_SET this_used;
|
||
if (!NONDEBUG_INSN_P (p_insn))
|
||
continue;
|
||
|
||
CLEAR_HARD_REG_SET (this_used);
|
||
note_uses (&PATTERN (p_insn), record_hard_reg_uses,
|
||
&this_used);
|
||
AND_COMPL_HARD_REG_SET (this_used, prologue_clobbered);
|
||
IOR_HARD_REG_SET (prologue_used, this_used);
|
||
note_stores (PATTERN (p_insn), record_hard_reg_sets,
|
||
&prologue_clobbered);
|
||
}
|
||
|
||
prepare_shrink_wrap (entry_edge->dest);
|
||
|
||
bitmap_initialize (&bb_antic_flags, &bitmap_default_obstack);
|
||
bitmap_initialize (&bb_on_list, &bitmap_default_obstack);
|
||
bitmap_initialize (&bb_tail, &bitmap_default_obstack);
|
||
|
||
/* Find the set of basic blocks that require a stack frame,
|
||
and blocks that are too big to be duplicated. */
|
||
|
||
vec = VEC_alloc (basic_block, heap, n_basic_blocks);
|
||
|
||
CLEAR_HARD_REG_SET (set_up_by_prologue.set);
|
||
add_to_hard_reg_set (&set_up_by_prologue.set, Pmode,
|
||
STACK_POINTER_REGNUM);
|
||
add_to_hard_reg_set (&set_up_by_prologue.set, Pmode, ARG_POINTER_REGNUM);
|
||
if (frame_pointer_needed)
|
||
add_to_hard_reg_set (&set_up_by_prologue.set, Pmode,
|
||
HARD_FRAME_POINTER_REGNUM);
|
||
if (pic_offset_table_rtx)
|
||
add_to_hard_reg_set (&set_up_by_prologue.set, Pmode,
|
||
PIC_OFFSET_TABLE_REGNUM);
|
||
if (stack_realign_drap && crtl->drap_reg)
|
||
add_to_hard_reg_set (&set_up_by_prologue.set,
|
||
GET_MODE (crtl->drap_reg),
|
||
REGNO (crtl->drap_reg));
|
||
if (targetm.set_up_by_prologue)
|
||
targetm.set_up_by_prologue (&set_up_by_prologue);
|
||
|
||
/* We don't use a different max size depending on
|
||
optimize_bb_for_speed_p because increasing shrink-wrapping
|
||
opportunities by duplicating tail blocks can actually result
|
||
in an overall decrease in code size. */
|
||
max_grow_size = get_uncond_jump_length ();
|
||
max_grow_size *= PARAM_VALUE (PARAM_MAX_GROW_COPY_BB_INSNS);
|
||
|
||
FOR_EACH_BB (bb)
|
||
{
|
||
rtx insn;
|
||
unsigned size = 0;
|
||
|
||
FOR_BB_INSNS (bb, insn)
|
||
if (NONDEBUG_INSN_P (insn))
|
||
{
|
||
if (requires_stack_frame_p (insn, prologue_used,
|
||
set_up_by_prologue.set))
|
||
{
|
||
if (bb == entry_edge->dest)
|
||
goto fail_shrinkwrap;
|
||
bitmap_set_bit (&bb_flags, bb->index);
|
||
VEC_quick_push (basic_block, vec, bb);
|
||
break;
|
||
}
|
||
else if (size <= max_grow_size)
|
||
{
|
||
size += get_attr_min_length (insn);
|
||
if (size > max_grow_size)
|
||
bitmap_set_bit (&bb_on_list, bb->index);
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Blocks that really need a prologue, or are too big for tails. */
|
||
bitmap_ior_into (&bb_on_list, &bb_flags);
|
||
|
||
/* For every basic block that needs a prologue, mark all blocks
|
||
reachable from it, so as to ensure they are also seen as
|
||
requiring a prologue. */
|
||
while (!VEC_empty (basic_block, vec))
|
||
{
|
||
basic_block tmp_bb = VEC_pop (basic_block, vec);
|
||
|
||
FOR_EACH_EDGE (e, ei, tmp_bb->succs)
|
||
if (e->dest != EXIT_BLOCK_PTR
|
||
&& bitmap_set_bit (&bb_flags, e->dest->index))
|
||
VEC_quick_push (basic_block, vec, e->dest);
|
||
}
|
||
|
||
/* Find the set of basic blocks that need no prologue, have a
|
||
single successor, can be duplicated, meet a max size
|
||
requirement, and go to the exit via like blocks. */
|
||
VEC_quick_push (basic_block, vec, EXIT_BLOCK_PTR);
|
||
while (!VEC_empty (basic_block, vec))
|
||
{
|
||
basic_block tmp_bb = VEC_pop (basic_block, vec);
|
||
|
||
FOR_EACH_EDGE (e, ei, tmp_bb->preds)
|
||
if (single_succ_p (e->src)
|
||
&& !bitmap_bit_p (&bb_on_list, e->src->index)
|
||
&& can_duplicate_block_p (e->src))
|
||
{
|
||
edge pe;
|
||
edge_iterator pei;
|
||
|
||
/* If there is predecessor of e->src which doesn't
|
||
need prologue and the edge is complex,
|
||
we might not be able to redirect the branch
|
||
to a copy of e->src. */
|
||
FOR_EACH_EDGE (pe, pei, e->src->preds)
|
||
if ((pe->flags & EDGE_COMPLEX) != 0
|
||
&& !bitmap_bit_p (&bb_flags, pe->src->index))
|
||
break;
|
||
if (pe == NULL && bitmap_set_bit (&bb_tail, e->src->index))
|
||
VEC_quick_push (basic_block, vec, e->src);
|
||
}
|
||
}
|
||
|
||
/* Now walk backwards from every block that is marked as needing
|
||
a prologue to compute the bb_antic_flags bitmap. Exclude
|
||
tail blocks; They can be duplicated to be used on paths not
|
||
needing a prologue. */
|
||
bitmap_clear (&bb_on_list);
|
||
bitmap_and_compl (&bb_antic_flags, &bb_flags, &bb_tail);
|
||
FOR_EACH_BB (bb)
|
||
{
|
||
if (!bitmap_bit_p (&bb_antic_flags, bb->index))
|
||
continue;
|
||
FOR_EACH_EDGE (e, ei, bb->preds)
|
||
if (!bitmap_bit_p (&bb_antic_flags, e->src->index)
|
||
&& bitmap_set_bit (&bb_on_list, e->src->index))
|
||
VEC_quick_push (basic_block, vec, e->src);
|
||
}
|
||
while (!VEC_empty (basic_block, vec))
|
||
{
|
||
basic_block tmp_bb = VEC_pop (basic_block, vec);
|
||
bool all_set = true;
|
||
|
||
bitmap_clear_bit (&bb_on_list, tmp_bb->index);
|
||
FOR_EACH_EDGE (e, ei, tmp_bb->succs)
|
||
if (!bitmap_bit_p (&bb_antic_flags, e->dest->index))
|
||
{
|
||
all_set = false;
|
||
break;
|
||
}
|
||
|
||
if (all_set)
|
||
{
|
||
bitmap_set_bit (&bb_antic_flags, tmp_bb->index);
|
||
FOR_EACH_EDGE (e, ei, tmp_bb->preds)
|
||
if (!bitmap_bit_p (&bb_antic_flags, e->src->index)
|
||
&& bitmap_set_bit (&bb_on_list, e->src->index))
|
||
VEC_quick_push (basic_block, vec, e->src);
|
||
}
|
||
}
|
||
/* Find exactly one edge that leads to a block in ANTIC from
|
||
a block that isn't. */
|
||
if (!bitmap_bit_p (&bb_antic_flags, entry_edge->dest->index))
|
||
FOR_EACH_BB (bb)
|
||
{
|
||
if (!bitmap_bit_p (&bb_antic_flags, bb->index))
|
||
continue;
|
||
FOR_EACH_EDGE (e, ei, bb->preds)
|
||
if (!bitmap_bit_p (&bb_antic_flags, e->src->index))
|
||
{
|
||
if (entry_edge != orig_entry_edge)
|
||
{
|
||
entry_edge = orig_entry_edge;
|
||
if (dump_file)
|
||
fprintf (dump_file, "More than one candidate edge.\n");
|
||
goto fail_shrinkwrap;
|
||
}
|
||
if (dump_file)
|
||
fprintf (dump_file, "Found candidate edge for "
|
||
"shrink-wrapping, %d->%d.\n", e->src->index,
|
||
e->dest->index);
|
||
entry_edge = e;
|
||
}
|
||
}
|
||
|
||
if (entry_edge != orig_entry_edge)
|
||
{
|
||
/* Test whether the prologue is known to clobber any register
|
||
(other than FP or SP) which are live on the edge. */
|
||
CLEAR_HARD_REG_BIT (prologue_clobbered, STACK_POINTER_REGNUM);
|
||
if (frame_pointer_needed)
|
||
CLEAR_HARD_REG_BIT (prologue_clobbered, HARD_FRAME_POINTER_REGNUM);
|
||
CLEAR_HARD_REG_SET (live_on_edge);
|
||
reg_set_to_hard_reg_set (&live_on_edge,
|
||
df_get_live_in (entry_edge->dest));
|
||
if (hard_reg_set_intersect_p (live_on_edge, prologue_clobbered))
|
||
{
|
||
entry_edge = orig_entry_edge;
|
||
if (dump_file)
|
||
fprintf (dump_file,
|
||
"Shrink-wrapping aborted due to clobber.\n");
|
||
}
|
||
}
|
||
if (entry_edge != orig_entry_edge)
|
||
{
|
||
crtl->shrink_wrapped = true;
|
||
if (dump_file)
|
||
fprintf (dump_file, "Performing shrink-wrapping.\n");
|
||
|
||
/* Find tail blocks reachable from both blocks needing a
|
||
prologue and blocks not needing a prologue. */
|
||
if (!bitmap_empty_p (&bb_tail))
|
||
FOR_EACH_BB (bb)
|
||
{
|
||
bool some_pro, some_no_pro;
|
||
if (!bitmap_bit_p (&bb_tail, bb->index))
|
||
continue;
|
||
some_pro = some_no_pro = false;
|
||
FOR_EACH_EDGE (e, ei, bb->preds)
|
||
{
|
||
if (bitmap_bit_p (&bb_flags, e->src->index))
|
||
some_pro = true;
|
||
else
|
||
some_no_pro = true;
|
||
}
|
||
if (some_pro && some_no_pro)
|
||
VEC_quick_push (basic_block, vec, bb);
|
||
else
|
||
bitmap_clear_bit (&bb_tail, bb->index);
|
||
}
|
||
/* Find the head of each tail. */
|
||
while (!VEC_empty (basic_block, vec))
|
||
{
|
||
basic_block tbb = VEC_pop (basic_block, vec);
|
||
|
||
if (!bitmap_bit_p (&bb_tail, tbb->index))
|
||
continue;
|
||
|
||
while (single_succ_p (tbb))
|
||
{
|
||
tbb = single_succ (tbb);
|
||
bitmap_clear_bit (&bb_tail, tbb->index);
|
||
}
|
||
}
|
||
/* Now duplicate the tails. */
|
||
if (!bitmap_empty_p (&bb_tail))
|
||
FOR_EACH_BB_REVERSE (bb)
|
||
{
|
||
basic_block copy_bb, tbb;
|
||
rtx insert_point;
|
||
int eflags;
|
||
|
||
if (!bitmap_clear_bit (&bb_tail, bb->index))
|
||
continue;
|
||
|
||
/* Create a copy of BB, instructions and all, for
|
||
use on paths that don't need a prologue.
|
||
Ideal placement of the copy is on a fall-thru edge
|
||
or after a block that would jump to the copy. */
|
||
FOR_EACH_EDGE (e, ei, bb->preds)
|
||
if (!bitmap_bit_p (&bb_flags, e->src->index)
|
||
&& single_succ_p (e->src))
|
||
break;
|
||
if (e)
|
||
{
|
||
copy_bb = create_basic_block (NEXT_INSN (BB_END (e->src)),
|
||
NULL_RTX, e->src);
|
||
BB_COPY_PARTITION (copy_bb, e->src);
|
||
}
|
||
else
|
||
{
|
||
/* Otherwise put the copy at the end of the function. */
|
||
copy_bb = create_basic_block (NULL_RTX, NULL_RTX,
|
||
EXIT_BLOCK_PTR->prev_bb);
|
||
BB_COPY_PARTITION (copy_bb, bb);
|
||
}
|
||
|
||
insert_point = emit_note_after (NOTE_INSN_DELETED,
|
||
BB_END (copy_bb));
|
||
emit_barrier_after (BB_END (copy_bb));
|
||
|
||
tbb = bb;
|
||
while (1)
|
||
{
|
||
dup_block_and_redirect (tbb, copy_bb, insert_point,
|
||
&bb_flags);
|
||
tbb = single_succ (tbb);
|
||
if (tbb == EXIT_BLOCK_PTR)
|
||
break;
|
||
e = split_block (copy_bb, PREV_INSN (insert_point));
|
||
copy_bb = e->dest;
|
||
}
|
||
|
||
/* Quiet verify_flow_info by (ab)using EDGE_FAKE.
|
||
We have yet to add a simple_return to the tails,
|
||
as we'd like to first convert_jumps_to_returns in
|
||
case the block is no longer used after that. */
|
||
eflags = EDGE_FAKE;
|
||
if (CALL_P (PREV_INSN (insert_point))
|
||
&& SIBLING_CALL_P (PREV_INSN (insert_point)))
|
||
eflags = EDGE_SIBCALL | EDGE_ABNORMAL;
|
||
make_single_succ_edge (copy_bb, EXIT_BLOCK_PTR, eflags);
|
||
|
||
/* verify_flow_info doesn't like a note after a
|
||
sibling call. */
|
||
delete_insn (insert_point);
|
||
if (bitmap_empty_p (&bb_tail))
|
||
break;
|
||
}
|
||
}
|
||
|
||
fail_shrinkwrap:
|
||
bitmap_clear (&bb_tail);
|
||
bitmap_clear (&bb_antic_flags);
|
||
bitmap_clear (&bb_on_list);
|
||
VEC_free (basic_block, heap, vec);
|
||
}
|
||
#endif
|
||
|
||
if (split_prologue_seq != NULL_RTX)
|
||
{
|
||
insert_insn_on_edge (split_prologue_seq, orig_entry_edge);
|
||
inserted = true;
|
||
}
|
||
if (prologue_seq != NULL_RTX)
|
||
{
|
||
insert_insn_on_edge (prologue_seq, entry_edge);
|
||
inserted = true;
|
||
}
|
||
|
||
/* If the exit block has no non-fake predecessors, we don't need
|
||
an epilogue. */
|
||
FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
|
||
if ((e->flags & EDGE_FAKE) == 0)
|
||
break;
|
||
if (e == NULL)
|
||
goto epilogue_done;
|
||
|
||
rtl_profile_for_bb (EXIT_BLOCK_PTR);
|
||
|
||
exit_fallthru_edge = find_fallthru_edge (EXIT_BLOCK_PTR->preds);
|
||
|
||
/* If we're allowed to generate a simple return instruction, then by
|
||
definition we don't need a full epilogue. If the last basic
|
||
block before the exit block does not contain active instructions,
|
||
examine its predecessors and try to emit (conditional) return
|
||
instructions. */
|
||
#ifdef HAVE_simple_return
|
||
if (entry_edge != orig_entry_edge)
|
||
{
|
||
if (optimize)
|
||
{
|
||
unsigned i, last;
|
||
|
||
/* convert_jumps_to_returns may add to EXIT_BLOCK_PTR->preds
|
||
(but won't remove). Stop at end of current preds. */
|
||
last = EDGE_COUNT (EXIT_BLOCK_PTR->preds);
|
||
for (i = 0; i < last; i++)
|
||
{
|
||
e = EDGE_I (EXIT_BLOCK_PTR->preds, i);
|
||
if (LABEL_P (BB_HEAD (e->src))
|
||
&& !bitmap_bit_p (&bb_flags, e->src->index)
|
||
&& !active_insn_between (BB_HEAD (e->src), BB_END (e->src)))
|
||
unconverted_simple_returns
|
||
= convert_jumps_to_returns (e->src, true,
|
||
unconverted_simple_returns);
|
||
}
|
||
}
|
||
|
||
if (exit_fallthru_edge != NULL
|
||
&& EDGE_COUNT (exit_fallthru_edge->src->preds) != 0
|
||
&& !bitmap_bit_p (&bb_flags, exit_fallthru_edge->src->index))
|
||
{
|
||
basic_block last_bb;
|
||
|
||
last_bb = emit_return_for_exit (exit_fallthru_edge, true);
|
||
returnjump = BB_END (last_bb);
|
||
exit_fallthru_edge = NULL;
|
||
}
|
||
}
|
||
#endif
|
||
#ifdef HAVE_return
|
||
if (HAVE_return)
|
||
{
|
||
if (exit_fallthru_edge == NULL)
|
||
goto epilogue_done;
|
||
|
||
if (optimize)
|
||
{
|
||
basic_block last_bb = exit_fallthru_edge->src;
|
||
|
||
if (LABEL_P (BB_HEAD (last_bb))
|
||
&& !active_insn_between (BB_HEAD (last_bb), BB_END (last_bb)))
|
||
convert_jumps_to_returns (last_bb, false, NULL);
|
||
|
||
if (EDGE_COUNT (last_bb->preds) != 0
|
||
&& single_succ_p (last_bb))
|
||
{
|
||
last_bb = emit_return_for_exit (exit_fallthru_edge, false);
|
||
epilogue_end = returnjump = BB_END (last_bb);
|
||
#ifdef HAVE_simple_return
|
||
/* Emitting the return may add a basic block.
|
||
Fix bb_flags for the added block. */
|
||
if (last_bb != exit_fallthru_edge->src)
|
||
bitmap_set_bit (&bb_flags, last_bb->index);
|
||
#endif
|
||
goto epilogue_done;
|
||
}
|
||
}
|
||
}
|
||
#endif
|
||
|
||
/* A small fib -- epilogue is not yet completed, but we wish to re-use
|
||
this marker for the splits of EH_RETURN patterns, and nothing else
|
||
uses the flag in the meantime. */
|
||
epilogue_completed = 1;
|
||
|
||
#ifdef HAVE_eh_return
|
||
/* Find non-fallthru edges that end with EH_RETURN instructions. On
|
||
some targets, these get split to a special version of the epilogue
|
||
code. In order to be able to properly annotate these with unwind
|
||
info, try to split them now. If we get a valid split, drop an
|
||
EPILOGUE_BEG note and mark the insns as epilogue insns. */
|
||
FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
|
||
{
|
||
rtx prev, last, trial;
|
||
|
||
if (e->flags & EDGE_FALLTHRU)
|
||
continue;
|
||
last = BB_END (e->src);
|
||
if (!eh_returnjump_p (last))
|
||
continue;
|
||
|
||
prev = PREV_INSN (last);
|
||
trial = try_split (PATTERN (last), last, 1);
|
||
if (trial == last)
|
||
continue;
|
||
|
||
record_insns (NEXT_INSN (prev), NEXT_INSN (trial), &epilogue_insn_hash);
|
||
emit_note_after (NOTE_INSN_EPILOGUE_BEG, prev);
|
||
}
|
||
#endif
|
||
|
||
/* If nothing falls through into the exit block, we don't need an
|
||
epilogue. */
|
||
|
||
if (exit_fallthru_edge == NULL)
|
||
goto epilogue_done;
|
||
|
||
#ifdef HAVE_epilogue
|
||
if (HAVE_epilogue)
|
||
{
|
||
start_sequence ();
|
||
epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
|
||
seq = gen_epilogue ();
|
||
if (seq)
|
||
emit_jump_insn (seq);
|
||
|
||
/* Retain a map of the epilogue insns. */
|
||
record_insns (seq, NULL, &epilogue_insn_hash);
|
||
set_insn_locators (seq, epilogue_locator);
|
||
|
||
seq = get_insns ();
|
||
returnjump = get_last_insn ();
|
||
end_sequence ();
|
||
|
||
insert_insn_on_edge (seq, exit_fallthru_edge);
|
||
inserted = true;
|
||
|
||
if (JUMP_P (returnjump))
|
||
set_return_jump_label (returnjump);
|
||
}
|
||
else
|
||
#endif
|
||
{
|
||
basic_block cur_bb;
|
||
|
||
if (! next_active_insn (BB_END (exit_fallthru_edge->src)))
|
||
goto epilogue_done;
|
||
/* We have a fall-through edge to the exit block, the source is not
|
||
at the end of the function, and there will be an assembler epilogue
|
||
at the end of the function.
|
||
We can't use force_nonfallthru here, because that would try to
|
||
use return. Inserting a jump 'by hand' is extremely messy, so
|
||
we take advantage of cfg_layout_finalize using
|
||
fixup_fallthru_exit_predecessor. */
|
||
cfg_layout_initialize (0);
|
||
FOR_EACH_BB (cur_bb)
|
||
if (cur_bb->index >= NUM_FIXED_BLOCKS
|
||
&& cur_bb->next_bb->index >= NUM_FIXED_BLOCKS)
|
||
cur_bb->aux = cur_bb->next_bb;
|
||
cfg_layout_finalize ();
|
||
}
|
||
|
||
epilogue_done:
|
||
|
||
default_rtl_profile ();
|
||
|
||
if (inserted)
|
||
{
|
||
sbitmap blocks;
|
||
|
||
commit_edge_insertions ();
|
||
|
||
/* Look for basic blocks within the prologue insns. */
|
||
blocks = sbitmap_alloc (last_basic_block);
|
||
sbitmap_zero (blocks);
|
||
SET_BIT (blocks, entry_edge->dest->index);
|
||
SET_BIT (blocks, orig_entry_edge->dest->index);
|
||
find_many_sub_basic_blocks (blocks);
|
||
sbitmap_free (blocks);
|
||
|
||
/* The epilogue insns we inserted may cause the exit edge to no longer
|
||
be fallthru. */
|
||
FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
|
||
{
|
||
if (((e->flags & EDGE_FALLTHRU) != 0)
|
||
&& returnjump_p (BB_END (e->src)))
|
||
e->flags &= ~EDGE_FALLTHRU;
|
||
}
|
||
}
|
||
|
||
#ifdef HAVE_simple_return
|
||
/* If there were branches to an empty LAST_BB which we tried to
|
||
convert to conditional simple_returns, but couldn't for some
|
||
reason, create a block to hold a simple_return insn and redirect
|
||
those remaining edges. */
|
||
if (!VEC_empty (edge, unconverted_simple_returns))
|
||
{
|
||
basic_block simple_return_block_hot = NULL;
|
||
basic_block simple_return_block_cold = NULL;
|
||
edge pending_edge_hot = NULL;
|
||
edge pending_edge_cold = NULL;
|
||
basic_block exit_pred = EXIT_BLOCK_PTR->prev_bb;
|
||
int i;
|
||
|
||
gcc_assert (entry_edge != orig_entry_edge);
|
||
|
||
/* See if we can reuse the last insn that was emitted for the
|
||
epilogue. */
|
||
if (returnjump != NULL_RTX
|
||
&& JUMP_LABEL (returnjump) == simple_return_rtx)
|
||
{
|
||
e = split_block (BLOCK_FOR_INSN (returnjump), PREV_INSN (returnjump));
|
||
if (BB_PARTITION (e->src) == BB_HOT_PARTITION)
|
||
simple_return_block_hot = e->dest;
|
||
else
|
||
simple_return_block_cold = e->dest;
|
||
}
|
||
|
||
/* Also check returns we might need to add to tail blocks. */
|
||
FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
|
||
if (EDGE_COUNT (e->src->preds) != 0
|
||
&& (e->flags & EDGE_FAKE) != 0
|
||
&& !bitmap_bit_p (&bb_flags, e->src->index))
|
||
{
|
||
if (BB_PARTITION (e->src) == BB_HOT_PARTITION)
|
||
pending_edge_hot = e;
|
||
else
|
||
pending_edge_cold = e;
|
||
}
|
||
|
||
FOR_EACH_VEC_ELT (edge, unconverted_simple_returns, i, e)
|
||
{
|
||
basic_block *pdest_bb;
|
||
edge pending;
|
||
|
||
if (BB_PARTITION (e->src) == BB_HOT_PARTITION)
|
||
{
|
||
pdest_bb = &simple_return_block_hot;
|
||
pending = pending_edge_hot;
|
||
}
|
||
else
|
||
{
|
||
pdest_bb = &simple_return_block_cold;
|
||
pending = pending_edge_cold;
|
||
}
|
||
|
||
if (*pdest_bb == NULL && pending != NULL)
|
||
{
|
||
emit_return_into_block (true, pending->src);
|
||
pending->flags &= ~(EDGE_FALLTHRU | EDGE_FAKE);
|
||
*pdest_bb = pending->src;
|
||
}
|
||
else if (*pdest_bb == NULL)
|
||
{
|
||
basic_block bb;
|
||
rtx start;
|
||
|
||
bb = create_basic_block (NULL, NULL, exit_pred);
|
||
BB_COPY_PARTITION (bb, e->src);
|
||
start = emit_jump_insn_after (gen_simple_return (),
|
||
BB_END (bb));
|
||
JUMP_LABEL (start) = simple_return_rtx;
|
||
emit_barrier_after (start);
|
||
|
||
*pdest_bb = bb;
|
||
make_edge (bb, EXIT_BLOCK_PTR, 0);
|
||
}
|
||
redirect_edge_and_branch_force (e, *pdest_bb);
|
||
}
|
||
VEC_free (edge, heap, unconverted_simple_returns);
|
||
}
|
||
|
||
if (entry_edge != orig_entry_edge)
|
||
{
|
||
FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
|
||
if (EDGE_COUNT (e->src->preds) != 0
|
||
&& (e->flags & EDGE_FAKE) != 0
|
||
&& !bitmap_bit_p (&bb_flags, e->src->index))
|
||
{
|
||
emit_return_into_block (true, e->src);
|
||
e->flags &= ~(EDGE_FALLTHRU | EDGE_FAKE);
|
||
}
|
||
}
|
||
#endif
|
||
|
||
#ifdef HAVE_sibcall_epilogue
|
||
/* Emit sibling epilogues before any sibling call sites. */
|
||
for (ei = ei_start (EXIT_BLOCK_PTR->preds); (e = ei_safe_edge (ei)); )
|
||
{
|
||
basic_block bb = e->src;
|
||
rtx insn = BB_END (bb);
|
||
rtx ep_seq;
|
||
|
||
if (!CALL_P (insn)
|
||
|| ! SIBLING_CALL_P (insn)
|
||
#ifdef HAVE_simple_return
|
||
|| (entry_edge != orig_entry_edge
|
||
&& !bitmap_bit_p (&bb_flags, bb->index))
|
||
#endif
|
||
)
|
||
{
|
||
ei_next (&ei);
|
||
continue;
|
||
}
|
||
|
||
ep_seq = gen_sibcall_epilogue ();
|
||
if (ep_seq)
|
||
{
|
||
start_sequence ();
|
||
emit_note (NOTE_INSN_EPILOGUE_BEG);
|
||
emit_insn (ep_seq);
|
||
seq = get_insns ();
|
||
end_sequence ();
|
||
|
||
/* Retain a map of the epilogue insns. Used in life analysis to
|
||
avoid getting rid of sibcall epilogue insns. Do this before we
|
||
actually emit the sequence. */
|
||
record_insns (seq, NULL, &epilogue_insn_hash);
|
||
set_insn_locators (seq, epilogue_locator);
|
||
|
||
emit_insn_before (seq, insn);
|
||
}
|
||
ei_next (&ei);
|
||
}
|
||
#endif
|
||
|
||
#ifdef HAVE_epilogue
|
||
if (epilogue_end)
|
||
{
|
||
rtx insn, next;
|
||
|
||
/* Similarly, move any line notes that appear after the epilogue.
|
||
There is no need, however, to be quite so anal about the existence
|
||
of such a note. Also possibly move
|
||
NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
|
||
info generation. */
|
||
for (insn = epilogue_end; insn; insn = next)
|
||
{
|
||
next = NEXT_INSN (insn);
|
||
if (NOTE_P (insn)
|
||
&& (NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG))
|
||
reorder_insns (insn, insn, PREV_INSN (epilogue_end));
|
||
}
|
||
}
|
||
#endif
|
||
|
||
#ifdef HAVE_simple_return
|
||
bitmap_clear (&bb_flags);
|
||
#endif
|
||
|
||
/* Threading the prologue and epilogue changes the artificial refs
|
||
in the entry and exit blocks. */
|
||
epilogue_completed = 1;
|
||
df_update_entry_exit_and_calls ();
|
||
}
|
||
|
||
/* Reposition the prologue-end and epilogue-begin notes after
|
||
instruction scheduling. */
|
||
|
||
void
|
||
reposition_prologue_and_epilogue_notes (void)
|
||
{
|
||
#if defined (HAVE_prologue) || defined (HAVE_epilogue) \
|
||
|| defined (HAVE_sibcall_epilogue)
|
||
/* Since the hash table is created on demand, the fact that it is
|
||
non-null is a signal that it is non-empty. */
|
||
if (prologue_insn_hash != NULL)
|
||
{
|
||
size_t len = htab_elements (prologue_insn_hash);
|
||
rtx insn, last = NULL, note = NULL;
|
||
|
||
/* Scan from the beginning until we reach the last prologue insn. */
|
||
/* ??? While we do have the CFG intact, there are two problems:
|
||
(1) The prologue can contain loops (typically probing the stack),
|
||
which means that the end of the prologue isn't in the first bb.
|
||
(2) Sometimes the PROLOGUE_END note gets pushed into the next bb. */
|
||
for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
|
||
{
|
||
if (NOTE_P (insn))
|
||
{
|
||
if (NOTE_KIND (insn) == NOTE_INSN_PROLOGUE_END)
|
||
note = insn;
|
||
}
|
||
else if (contains (insn, prologue_insn_hash))
|
||
{
|
||
last = insn;
|
||
if (--len == 0)
|
||
break;
|
||
}
|
||
}
|
||
|
||
if (last)
|
||
{
|
||
if (note == NULL)
|
||
{
|
||
/* Scan forward looking for the PROLOGUE_END note. It should
|
||
be right at the beginning of the block, possibly with other
|
||
insn notes that got moved there. */
|
||
for (note = NEXT_INSN (last); ; note = NEXT_INSN (note))
|
||
{
|
||
if (NOTE_P (note)
|
||
&& NOTE_KIND (note) == NOTE_INSN_PROLOGUE_END)
|
||
break;
|
||
}
|
||
}
|
||
|
||
/* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
|
||
if (LABEL_P (last))
|
||
last = NEXT_INSN (last);
|
||
reorder_insns (note, note, last);
|
||
}
|
||
}
|
||
|
||
if (epilogue_insn_hash != NULL)
|
||
{
|
||
edge_iterator ei;
|
||
edge e;
|
||
|
||
FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
|
||
{
|
||
rtx insn, first = NULL, note = NULL;
|
||
basic_block bb = e->src;
|
||
|
||
/* Scan from the beginning until we reach the first epilogue insn. */
|
||
FOR_BB_INSNS (bb, insn)
|
||
{
|
||
if (NOTE_P (insn))
|
||
{
|
||
if (NOTE_KIND (insn) == NOTE_INSN_EPILOGUE_BEG)
|
||
{
|
||
note = insn;
|
||
if (first != NULL)
|
||
break;
|
||
}
|
||
}
|
||
else if (first == NULL && contains (insn, epilogue_insn_hash))
|
||
{
|
||
first = insn;
|
||
if (note != NULL)
|
||
break;
|
||
}
|
||
}
|
||
|
||
if (note)
|
||
{
|
||
/* If the function has a single basic block, and no real
|
||
epilogue insns (e.g. sibcall with no cleanup), the
|
||
epilogue note can get scheduled before the prologue
|
||
note. If we have frame related prologue insns, having
|
||
them scanned during the epilogue will result in a crash.
|
||
In this case re-order the epilogue note to just before
|
||
the last insn in the block. */
|
||
if (first == NULL)
|
||
first = BB_END (bb);
|
||
|
||
if (PREV_INSN (first) != note)
|
||
reorder_insns (note, note, PREV_INSN (first));
|
||
}
|
||
}
|
||
}
|
||
#endif /* HAVE_prologue or HAVE_epilogue */
|
||
}
|
||
|
||
/* Returns the name of function FN. */
|
||
const char *
|
||
function_name (struct function *fn)
|
||
{
|
||
if (fn == NULL)
|
||
return "(nofn)";
|
||
return lang_hooks.decl_printable_name (fn->decl, 2);
|
||
}
|
||
|
||
/* Returns the name of the current function. */
|
||
const char *
|
||
current_function_name (void)
|
||
{
|
||
return function_name (cfun);
|
||
}
|
||
|
||
|
||
static unsigned int
|
||
rest_of_handle_check_leaf_regs (void)
|
||
{
|
||
#ifdef LEAF_REGISTERS
|
||
crtl->uses_only_leaf_regs
|
||
= optimize > 0 && only_leaf_regs_used () && leaf_function_p ();
|
||
#endif
|
||
return 0;
|
||
}
|
||
|
||
/* Insert a TYPE into the used types hash table of CFUN. */
|
||
|
||
static void
|
||
used_types_insert_helper (tree type, struct function *func)
|
||
{
|
||
if (type != NULL && func != NULL)
|
||
{
|
||
void **slot;
|
||
|
||
if (func->used_types_hash == NULL)
|
||
func->used_types_hash = htab_create_ggc (37, htab_hash_pointer,
|
||
htab_eq_pointer, NULL);
|
||
slot = htab_find_slot (func->used_types_hash, type, INSERT);
|
||
if (*slot == NULL)
|
||
*slot = type;
|
||
}
|
||
}
|
||
|
||
/* Given a type, insert it into the used hash table in cfun. */
|
||
void
|
||
used_types_insert (tree t)
|
||
{
|
||
while (POINTER_TYPE_P (t) || TREE_CODE (t) == ARRAY_TYPE)
|
||
if (TYPE_NAME (t))
|
||
break;
|
||
else
|
||
t = TREE_TYPE (t);
|
||
if (TREE_CODE (t) == ERROR_MARK)
|
||
return;
|
||
if (TYPE_NAME (t) == NULL_TREE
|
||
|| TYPE_NAME (t) == TYPE_NAME (TYPE_MAIN_VARIANT (t)))
|
||
t = TYPE_MAIN_VARIANT (t);
|
||
if (debug_info_level > DINFO_LEVEL_NONE)
|
||
{
|
||
if (cfun)
|
||
used_types_insert_helper (t, cfun);
|
||
else
|
||
/* So this might be a type referenced by a global variable.
|
||
Record that type so that we can later decide to emit its debug
|
||
information. */
|
||
VEC_safe_push (tree, gc, types_used_by_cur_var_decl, t);
|
||
}
|
||
}
|
||
|
||
/* Helper to Hash a struct types_used_by_vars_entry. */
|
||
|
||
static hashval_t
|
||
hash_types_used_by_vars_entry (const struct types_used_by_vars_entry *entry)
|
||
{
|
||
gcc_assert (entry && entry->var_decl && entry->type);
|
||
|
||
return iterative_hash_object (entry->type,
|
||
iterative_hash_object (entry->var_decl, 0));
|
||
}
|
||
|
||
/* Hash function of the types_used_by_vars_entry hash table. */
|
||
|
||
hashval_t
|
||
types_used_by_vars_do_hash (const void *x)
|
||
{
|
||
const struct types_used_by_vars_entry *entry =
|
||
(const struct types_used_by_vars_entry *) x;
|
||
|
||
return hash_types_used_by_vars_entry (entry);
|
||
}
|
||
|
||
/*Equality function of the types_used_by_vars_entry hash table. */
|
||
|
||
int
|
||
types_used_by_vars_eq (const void *x1, const void *x2)
|
||
{
|
||
const struct types_used_by_vars_entry *e1 =
|
||
(const struct types_used_by_vars_entry *) x1;
|
||
const struct types_used_by_vars_entry *e2 =
|
||
(const struct types_used_by_vars_entry *)x2;
|
||
|
||
return (e1->var_decl == e2->var_decl && e1->type == e2->type);
|
||
}
|
||
|
||
/* Inserts an entry into the types_used_by_vars_hash hash table. */
|
||
|
||
void
|
||
types_used_by_var_decl_insert (tree type, tree var_decl)
|
||
{
|
||
if (type != NULL && var_decl != NULL)
|
||
{
|
||
void **slot;
|
||
struct types_used_by_vars_entry e;
|
||
e.var_decl = var_decl;
|
||
e.type = type;
|
||
if (types_used_by_vars_hash == NULL)
|
||
types_used_by_vars_hash =
|
||
htab_create_ggc (37, types_used_by_vars_do_hash,
|
||
types_used_by_vars_eq, NULL);
|
||
slot = htab_find_slot_with_hash (types_used_by_vars_hash, &e,
|
||
hash_types_used_by_vars_entry (&e), INSERT);
|
||
if (*slot == NULL)
|
||
{
|
||
struct types_used_by_vars_entry *entry;
|
||
entry = ggc_alloc_types_used_by_vars_entry ();
|
||
entry->type = type;
|
||
entry->var_decl = var_decl;
|
||
*slot = entry;
|
||
}
|
||
}
|
||
}
|
||
|
||
struct rtl_opt_pass pass_leaf_regs =
|
||
{
|
||
{
|
||
RTL_PASS,
|
||
"*leaf_regs", /* name */
|
||
NULL, /* gate */
|
||
rest_of_handle_check_leaf_regs, /* execute */
|
||
NULL, /* sub */
|
||
NULL, /* next */
|
||
0, /* static_pass_number */
|
||
TV_NONE, /* tv_id */
|
||
0, /* properties_required */
|
||
0, /* properties_provided */
|
||
0, /* properties_destroyed */
|
||
0, /* todo_flags_start */
|
||
0 /* todo_flags_finish */
|
||
}
|
||
};
|
||
|
||
static unsigned int
|
||
rest_of_handle_thread_prologue_and_epilogue (void)
|
||
{
|
||
if (optimize)
|
||
cleanup_cfg (CLEANUP_EXPENSIVE);
|
||
|
||
/* On some machines, the prologue and epilogue code, or parts thereof,
|
||
can be represented as RTL. Doing so lets us schedule insns between
|
||
it and the rest of the code and also allows delayed branch
|
||
scheduling to operate in the epilogue. */
|
||
thread_prologue_and_epilogue_insns ();
|
||
|
||
/* The stack usage info is finalized during prologue expansion. */
|
||
if (flag_stack_usage_info)
|
||
output_stack_usage ();
|
||
|
||
return 0;
|
||
}
|
||
|
||
struct rtl_opt_pass pass_thread_prologue_and_epilogue =
|
||
{
|
||
{
|
||
RTL_PASS,
|
||
"pro_and_epilogue", /* name */
|
||
NULL, /* gate */
|
||
rest_of_handle_thread_prologue_and_epilogue, /* execute */
|
||
NULL, /* sub */
|
||
NULL, /* next */
|
||
0, /* static_pass_number */
|
||
TV_THREAD_PROLOGUE_AND_EPILOGUE, /* tv_id */
|
||
0, /* properties_required */
|
||
0, /* properties_provided */
|
||
0, /* properties_destroyed */
|
||
TODO_verify_flow, /* todo_flags_start */
|
||
TODO_df_verify |
|
||
TODO_df_finish | TODO_verify_rtl_sharing |
|
||
TODO_ggc_collect /* todo_flags_finish */
|
||
}
|
||
};
|
||
|
||
|
||
/* This mini-pass fixes fall-out from SSA in asm statements that have
|
||
in-out constraints. Say you start with
|
||
|
||
orig = inout;
|
||
asm ("": "+mr" (inout));
|
||
use (orig);
|
||
|
||
which is transformed very early to use explicit output and match operands:
|
||
|
||
orig = inout;
|
||
asm ("": "=mr" (inout) : "0" (inout));
|
||
use (orig);
|
||
|
||
Or, after SSA and copyprop,
|
||
|
||
asm ("": "=mr" (inout_2) : "0" (inout_1));
|
||
use (inout_1);
|
||
|
||
Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
|
||
they represent two separate values, so they will get different pseudo
|
||
registers during expansion. Then, since the two operands need to match
|
||
per the constraints, but use different pseudo registers, reload can
|
||
only register a reload for these operands. But reloads can only be
|
||
satisfied by hardregs, not by memory, so we need a register for this
|
||
reload, just because we are presented with non-matching operands.
|
||
So, even though we allow memory for this operand, no memory can be
|
||
used for it, just because the two operands don't match. This can
|
||
cause reload failures on register-starved targets.
|
||
|
||
So it's a symptom of reload not being able to use memory for reloads
|
||
or, alternatively it's also a symptom of both operands not coming into
|
||
reload as matching (in which case the pseudo could go to memory just
|
||
fine, as the alternative allows it, and no reload would be necessary).
|
||
We fix the latter problem here, by transforming
|
||
|
||
asm ("": "=mr" (inout_2) : "0" (inout_1));
|
||
|
||
back to
|
||
|
||
inout_2 = inout_1;
|
||
asm ("": "=mr" (inout_2) : "0" (inout_2)); */
|
||
|
||
static void
|
||
match_asm_constraints_1 (rtx insn, rtx *p_sets, int noutputs)
|
||
{
|
||
int i;
|
||
bool changed = false;
|
||
rtx op = SET_SRC (p_sets[0]);
|
||
int ninputs = ASM_OPERANDS_INPUT_LENGTH (op);
|
||
rtvec inputs = ASM_OPERANDS_INPUT_VEC (op);
|
||
bool *output_matched = XALLOCAVEC (bool, noutputs);
|
||
|
||
memset (output_matched, 0, noutputs * sizeof (bool));
|
||
for (i = 0; i < ninputs; i++)
|
||
{
|
||
rtx input, output, insns;
|
||
const char *constraint = ASM_OPERANDS_INPUT_CONSTRAINT (op, i);
|
||
char *end;
|
||
int match, j;
|
||
|
||
if (*constraint == '%')
|
||
constraint++;
|
||
|
||
match = strtoul (constraint, &end, 10);
|
||
if (end == constraint)
|
||
continue;
|
||
|
||
gcc_assert (match < noutputs);
|
||
output = SET_DEST (p_sets[match]);
|
||
input = RTVEC_ELT (inputs, i);
|
||
/* Only do the transformation for pseudos. */
|
||
if (! REG_P (output)
|
||
|| rtx_equal_p (output, input)
|
||
|| (GET_MODE (input) != VOIDmode
|
||
&& GET_MODE (input) != GET_MODE (output)))
|
||
continue;
|
||
|
||
/* We can't do anything if the output is also used as input,
|
||
as we're going to overwrite it. */
|
||
for (j = 0; j < ninputs; j++)
|
||
if (reg_overlap_mentioned_p (output, RTVEC_ELT (inputs, j)))
|
||
break;
|
||
if (j != ninputs)
|
||
continue;
|
||
|
||
/* Avoid changing the same input several times. For
|
||
asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
|
||
only change in once (to out1), rather than changing it
|
||
first to out1 and afterwards to out2. */
|
||
if (i > 0)
|
||
{
|
||
for (j = 0; j < noutputs; j++)
|
||
if (output_matched[j] && input == SET_DEST (p_sets[j]))
|
||
break;
|
||
if (j != noutputs)
|
||
continue;
|
||
}
|
||
output_matched[match] = true;
|
||
|
||
start_sequence ();
|
||
emit_move_insn (output, input);
|
||
insns = get_insns ();
|
||
end_sequence ();
|
||
emit_insn_before (insns, insn);
|
||
|
||
/* Now replace all mentions of the input with output. We can't
|
||
just replace the occurrence in inputs[i], as the register might
|
||
also be used in some other input (or even in an address of an
|
||
output), which would mean possibly increasing the number of
|
||
inputs by one (namely 'output' in addition), which might pose
|
||
a too complicated problem for reload to solve. E.g. this situation:
|
||
|
||
asm ("" : "=r" (output), "=m" (input) : "0" (input))
|
||
|
||
Here 'input' is used in two occurrences as input (once for the
|
||
input operand, once for the address in the second output operand).
|
||
If we would replace only the occurrence of the input operand (to
|
||
make the matching) we would be left with this:
|
||
|
||
output = input
|
||
asm ("" : "=r" (output), "=m" (input) : "0" (output))
|
||
|
||
Now we suddenly have two different input values (containing the same
|
||
value, but different pseudos) where we formerly had only one.
|
||
With more complicated asms this might lead to reload failures
|
||
which wouldn't have happen without this pass. So, iterate over
|
||
all operands and replace all occurrences of the register used. */
|
||
for (j = 0; j < noutputs; j++)
|
||
if (!rtx_equal_p (SET_DEST (p_sets[j]), input)
|
||
&& reg_overlap_mentioned_p (input, SET_DEST (p_sets[j])))
|
||
SET_DEST (p_sets[j]) = replace_rtx (SET_DEST (p_sets[j]),
|
||
input, output);
|
||
for (j = 0; j < ninputs; j++)
|
||
if (reg_overlap_mentioned_p (input, RTVEC_ELT (inputs, j)))
|
||
RTVEC_ELT (inputs, j) = replace_rtx (RTVEC_ELT (inputs, j),
|
||
input, output);
|
||
|
||
changed = true;
|
||
}
|
||
|
||
if (changed)
|
||
df_insn_rescan (insn);
|
||
}
|
||
|
||
static unsigned
|
||
rest_of_match_asm_constraints (void)
|
||
{
|
||
basic_block bb;
|
||
rtx insn, pat, *p_sets;
|
||
int noutputs;
|
||
|
||
if (!crtl->has_asm_statement)
|
||
return 0;
|
||
|
||
df_set_flags (DF_DEFER_INSN_RESCAN);
|
||
FOR_EACH_BB (bb)
|
||
{
|
||
FOR_BB_INSNS (bb, insn)
|
||
{
|
||
if (!INSN_P (insn))
|
||
continue;
|
||
|
||
pat = PATTERN (insn);
|
||
if (GET_CODE (pat) == PARALLEL)
|
||
p_sets = &XVECEXP (pat, 0, 0), noutputs = XVECLEN (pat, 0);
|
||
else if (GET_CODE (pat) == SET)
|
||
p_sets = &PATTERN (insn), noutputs = 1;
|
||
else
|
||
continue;
|
||
|
||
if (GET_CODE (*p_sets) == SET
|
||
&& GET_CODE (SET_SRC (*p_sets)) == ASM_OPERANDS)
|
||
match_asm_constraints_1 (insn, p_sets, noutputs);
|
||
}
|
||
}
|
||
|
||
return TODO_df_finish;
|
||
}
|
||
|
||
struct rtl_opt_pass pass_match_asm_constraints =
|
||
{
|
||
{
|
||
RTL_PASS,
|
||
"asmcons", /* name */
|
||
NULL, /* gate */
|
||
rest_of_match_asm_constraints, /* execute */
|
||
NULL, /* sub */
|
||
NULL, /* next */
|
||
0, /* static_pass_number */
|
||
TV_NONE, /* tv_id */
|
||
0, /* properties_required */
|
||
0, /* properties_provided */
|
||
0, /* properties_destroyed */
|
||
0, /* todo_flags_start */
|
||
0 /* todo_flags_finish */
|
||
}
|
||
};
|
||
|
||
|
||
#include "gt-function.h"
|